Three months before saboteurs bombed the Nord Stream natural gas pipeline, the Biden administration learned from a close ally that the Ukrainian military had planned a covert attack on the undersea network, using a small team of divers who reported directly to the commander in chief of the Ukrainian armed forces.

Details about the plan, which have not been previously reported, were collected by a European intelligence service and shared with the CIA in June 2022. They provide some of the most specific evidence to date linking the Ukrainian government to the eventual attack in the Baltic Sea, which U.S. and Western officials have called a brazen and dangerous act of sabotage on Europe’s energy infrastructure.

The European intelligence reporting was shared on the chat platform Discord, allegedly by Air National Guard member Jack Teixeira. The Washington Post obtained a copy from one of Teixeira’s online friends.

The intelligence report was based on information obtained from an individual in Ukraine. The source’s information could not be corroborated immediately, but the CIA shared the report with Germany and other European countries last June, according to multiple officials familiar with the matter, who spoke on the condition of anonymity to discuss sensitive intelligence operations and diplomatic discussions.

The highly specific details, which include numbers of operatives and methods of attack, show Western allies had a basis to suspect Kyiv in the sabotage for nearly a year. That assessment has only strengthened in recent months as German law enforcement investigators uncovered evidence about the bombing that bears striking similarities to what the European service said Ukraine was planning.

Officials in multiple countries confirmed that the intelligence summary posted on Discord accurately stated what the European service told the CIA. The Post agreed to withhold the name of the European country and some aspects of the suspected plan at the request of government officials, who said exposing the information would threaten sources and operations.

Ukrainian officials, who have previously denied the country was involved in the Nord Stream attack, did not respond to requests for comment.

The White House declined to comment on a detailed set of questions about the European report and alleged Ukrainian military plot, including whether U.S. officials tried to stop the mission from proceeding.

The CIA also declined to comment.

On Sept. 26, 2022, three underwater explosions caused massive leaks on the Nord Stream 1 and 2 pipelines, leaving only one of the four gas links in the network intact. Some Biden administration officials initially suggested that Russia was to blame for what President Biden called “a deliberate act of sabotage,” promising that the United States would work with its allies “to get to the bottom of exactly what ... happened.” With winter approaching, it appeared the Kremlin might have intended to strangle the flow of energy, an act of “blackmail,” some leaders said, designed to intimidate European countries into withdrawing their financial and military support for Ukraine, and refraining from further sanctions.

Biden administration officials now privately concede there is no evidence that conclusively points to Moscow’s involvement, but publicly they have deflected questions about who might be responsible. European officials in several countries have quietly suggested that Ukraine was behind the attack but resisted publicly saying so over fears that blaming Kyiv could fracture the alliance against Russia. At gatherings of European and NATO policymakers, officials have settled into a rhythm as one senior European diplomat said recently, “Don’t talk about Nord Stream.”

The European intelligence made clear that the would-be attackers were not rogue operatives. All those involved reported directly to Gen. Valerii Zaluzhnyi, the country’s highest-ranking military officer, who was put in charge so that Ukraine’s president, Volodymyr Zelenskyy, would not know about the operation, the intelligence report said.

Keeping Zelenskyy out of the loop would have given the Ukrainian leader a plausible way to deny involvement in an audacious attack on civilian infrastructure that could ignite public outrage and jeopardize Western support to Ukraine — particularly in Germany, which got half its natural gas from Russia before the war and had long championed the project in the face of opposition from other European allies.

While Gazprom, the Russian state-owned gas conglomerate, owns 51% of Nord Stream, Western energy companies, including from Germany, France and the Netherlands, are partners and invested billions in the pipelines. Ukraine had long complained that Nord Stream would allow Russia to bypass Ukrainian pipes depriving Kyiv of huge transit revenue.

The intelligence summary says the Ukrainian military operation was “put on hold,” for reasons that remain unclear. The Ukrainians had planned to attack the pipeline on the heels of a major allied naval exercise, known as BALTOPS, which ran from June 5 to 17, 2022, according to the report.

However, according to German law enforcement officials investigating the September Nord Stream bombing, key details emerging of that operation line up with the earlier plot.

For instance, the Ukrainian individual who informed the European intelligence service in June said six members of Ukraine’s special operations forces using false identities intended to rent a boat and, using a submersible vehicle, dive to the floor of the Baltic Sea then damage or destroy the pipeline and escape undetected. In addition to oxygen, the team planned to bring helium, which is recommended for especially deep dives.

German investigators now believe that six individuals using fake passports rented a sailing yacht in September, embarked from Germany and planted explosives that severed the pipelines, according to officials familiar with that investigation. They believe the operatives were skilled divers, given that the explosives were planted at a depth of about 240 feet, in the range that experts say helium would be helpful for maintaining mental focus.

Investigators have matched explosive residue found on the pipeline to traces found inside the cabin of the yacht, called Andromeda, and they have linked Ukrainian individuals to the rental of the boat via an apparent front company in Poland. Investigators also suspect that at least one individual who serves in the Ukrainian military was involved in the sabotage operation.

A collaboration of German media organizations previously reported the suspected involvement of the Ukrainian military service member.

The June plot differs from the September attack in some respects. The European intelligence report notes that the Ukrainian operatives planned to attack the Nord Stream 1 pipeline, but it makes no mention of Nord Stream 2, a newer line. The intelligence report also says the saboteurs would embark from a different location in Europe, not Warnemünde, a German port town on the Baltic, where Andromeda was rented.

The CIA initially questioned the credibility of the information, in part because the source in Ukraine who provided the details had not yet established a track record of producing reliable information, according to officials familiar with the matter. The European service, a trusted U.S. partner, felt that the source was reliable.

However, despite any reservations the CIA might have had, the agency communicated the June intelligence to counterparts in Germany and other European countries, officials said. The European service also shared it with Germany, one person said. German intelligence personnel briefed lawmakers in Berlin in late June before they left for their summer break, according to an official with knowledge of the closed-door presentation.

Officials familiar with the European report conceded that it is possible that the suspected Ukrainian plotters might have been apprised that the intelligence was shared with several countries and that they may have changed some elements of the plan.

The report from the European intelligence service, however, was not the only piece of evidence pointing to Kyiv’s role in the pipeline bombing.

The Post previously reported that governments investigating the explosions uncovered communications that showed pro-Ukraine individuals or entities discussed the possibility of carrying out an attack on the Nord Stream pipelines. Those conversations took place before the attack but were only discovered in its aftermath, when spy agencies scoured data for possible clues, a senior Western security official said.

Despite waiving Trump-era sanctions on the Russia-to-Germany natural gas pipeline as an attempt to mend fences with Berlin, the Biden administration had long harbored concerns about Nord Stream and did not shed tears over its September demise.

After months of pressure from Washington, the German government halted final authorization of Nord Stream 2 just days before Russian forces invaded Ukraine in February 2022, surprising many U.S. and European officials who had worried Berlin would find Russia too important an energy source to sever ties. At the time of the attack, the pipeline was intact and had already been pumped full with 79 billion gallons of natural gas to ready it for operations.

Nearly a month before the rupture, the Russian energy giant Gazprom stopped flows on Nord Stream 1, hours after the Group of Seven industrialized nations announced a forthcoming price cap on Russian oil, a move intended to put a dent in the Kremlin’s treasury.

Officials have said the cost of repairing the pipelines would run into the hundreds of millions of dollars.

While U.S. intelligence officials were initially skeptical of the European reporting, they have long been concerned about aggressive operations by Ukraine that could escalate the war into a direct conflict between Russia and the United States and its NATO allies.

This February, on the eve of the war’s first anniversary, Ukraine’s military intelligence agency agreed, “at Washington’s request,” to postpone planned strikes on Moscow, according to another intelligence document leaked on Discord. That incident illustrated a broader tension that has existed throughout the war: Ukraine, eager to bring the fight to Russia’s home turf, is sometimes restrained by the United States.

Officials in Washington and Europe have admonished Ukraine for attacks outside its territory that they felt went too far. After a car bomb near Moscow in August killed Daria Dugina, in an attack that appeared intended for her father — a prominent Russian nationalist whose writing had helped to shape a Kremlin narrative about Ukraine — Western officials said they made clear to Zelenskyy that they held operatives in his government responsible. The attack was seen as provocative and risked a severe Russian response, officials said.

Ukraine has persisted with strikes inside Russia, including drone strikes on an airfield and on targets in Moscow that U.S. officials have linked to Kyiv.

The Washington Post’s Samuel Oakford, Isabelle Khurshudyan, Michael Birnbaum and Greg Miller contributed to this report.

previous coverage

• Investigators skeptical of yacht's role in Nord Stream bombing
• Russia, blaming US sabotage, calls for UN probe of Nord Stream 

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