KYIV, Ukraine — Ukraine’s ability to expel Russian forces from its country as soon as possible now depends largely on Germany and its willingness to send desperately needed armor, a senior adviser to President Volodymyr Zelensky said Tuesday.

But Germany is balking, causing deep frustration in Kyiv. It is an echo of the earliest days of the invasion, when Berlin was derided for offering helmets when Ukraine needed heavy weapons.

“Germany needs to understand that the timeline for the end of the war is dependent on its position,” Mykhailo Podolyak, a top adviser to Zelensky, told The Washington Post in an interview on Tuesday.

A sweeping counteroffensive in the northeastern Kharkiv region has forced Russian soldiers into a hasty retreat and returned more than 1,100 square miles to Ukrainian control, a potential turning point more than six months into the war.

Kyiv believes the requested heavy armor — including battle tanks and personnel carriers — could help shift that turning point into a tipping point. Ukrainian officials are now urging their Western partners to provide them with more weapons immediately.

“The faster we receive this or that weapon from Germany, the faster Germany finally breaks this feeling of closeness with Russia, the faster the war will end,” Podolyak said. He said that Ukraine is specifically asking for armored personnel vehicles and tanks to be able to support its battlefield momentum.

But Germany, so far, has been unwilling to grant the request. The German government did not respond to a request for comment on Tuesday night, but has emphasized it is coordinating its response with allies.

“No country has delivered Western-built infantry fighting vehicles or main battle tanks so far,” German Defense Minister Christine Lambrecht said in an event in Berlin this week. “We have agreed with our partners that Germany will not take such action unilaterally.”

In a Monday news conference with visiting Israeli Prime Minister Yair Lapid, Chancellor Olaf Scholz listed what he called “extensive” German weaponry already supplied, saying it had been crucial in the success of the counteroffensive.

Virtually no outside nations have provided tanks to Ukraine, instead sending aging models such as the M113, an armored personnel carrier with tracks that was first fielded by the United States in the 1960s. Denmark provided 54 M113s that were upgraded by Germany and then sent to Ukraine, according to the German defense ministry.

Poland and the Czech Republic have sent a few hundred Soviet-era T-72 tanks to Ukraine, with Germany promising to backfill their supplies. There is little doubt now that Ukraine could make use of more modern equipment, even if it would require further training.

On Monday, a senior U.S. defense official, speaking on the condition of anonymity under ground rules set by the Pentagon, said that the Ukrainians have shown in their counteroffensive that they are “quite effective” while using armored vehicles.

“So clearly, that kind of capability is important,” the defense official said, adding that the United States does not have any “specific plans about a specific capability at this point.”

Since the first days of Russia’s military offensive, Germany has been accused of dragging its feet on arms deliveries to Kyiv. Initially, as Russian troops massed on Ukraine’s borders, Berlin said its unique world war history, and long-standing policy, meant it could not send weapons.

Days after Russian President Vladimir Putin’s invasion, as part of what was seen as a sea-change in the country’s defense policy, Germany said it would send arms. But the government, led by Scholz, a social democrat, has still agonized over sending heavier weapons, and since then has been criticized for the speed and scope of deliveries.

Under public and political pressure, Berlin in April announced that it had approved shipping German-made self-propelled antiaircraft guns to Ukraine, with 24 sent so far. But it has resisted calls to send tanks, including the German-made Leopard 2.

According to German media reports, the manufacturer has 100 ready to send.

During a visit to Kyiv on Saturday, German Foreign Minister Annalena Baerbock told the Yalta European Strategy conference that Germany is “150 percent at the side of Ukraine and the people of Ukraine.”

But in a joint news conference with her Ukrainian counterpart, Dmytro Kuleba, Baerbock did not commit to supplying the equipment that Kyiv has been requesting. “As the situation on the ground changes, we are reexamining our support and will discuss further steps,” she said.

In a tweet on Tuesday, Kuleba echoed Podolyak, adding that Ukraine was also hoping for Marder infantry fighting vehicles. The Leopard is a tank operated by numerous NATO allies, including Canada, Poland and Turkey, while the Marder is an armored vehicle with tracks that carries infantrymen and does not have a large-caliber “main gun.”

“Disappointing signals from Germany while Ukraine needs Leopards and Marders now - to liberate people and save them from genocide,” Kuleba wrote. “Not a single rational argument on why these weapons cannot be supplied, only abstract fears and excuses. What is Berlin afraid of that Kyiv is not?”

Scholz’s center-left Social Democrats have historically espoused a policy of detente toward Russia, while the chancellor himself is known for an extremely cautious public style.

His government has voiced various arguments for resisting pressure to expand arms deliveries — from not wanting to trigger World War III, to saying Ukrainian troops would need training in order to operate modern weaponry. But often the statements have been contradictory.

Germany had initially said it could not spare any of its Marder infantry fighting vehicles, but later pursued a deal to send them to Slovenia so the eastern European country could send its own Soviet-era tanks onto Ukraine. Berlin entered into a similar arrangement with Poland and the Czech Republic, a swap system meant to get tanks to Ukrainian forces more quickly, but those efforts have largely stalled.

Scholz says he is carefully coordinating deliveries with western partners. And in a 90-minute call with Putin on Tuesday, Scholz said he stressed that Russia must withdraw its troops and respect Ukraine’s territorial sovereignty. But even among NATO allies there appears to be some frustration with Berlin.

In an interview with German television station ZDF on Monday, U.S. Ambassador to Germany Amy Gutmann said she welcomed Germany’s efforts in support of Ukraine but “my expectations are even higher.”

The war in Ukraine has posed a challenge to Germany’s standing in Europe.

In the early days of the war, Germany, long dependent on Russian fossil fuel, was a notable sanctions holdout, particularly on energy. The Baltic nations and Poland called for a full and immediate energy embargo. Germany and others opposed the idea, arguing it would hurt Europe more than the Kremlin.

Though evidence of Russian atrocities in Bucha helped get Germany and the rest of the bloc to phase out most oil imports from Russia, frustration with Berlin has lingered, particularly in Ukraine and among central and eastern European states.

In April, Zelensky rebuffed the offer of a visit from German President Frank-Walter Steinmeier, who has a complicated history with Ukraine because of his role in the failed Minsk peace accords.

In a recent interview with Der Spiegel, Polish Prime Minister Mateusz Morawiecki called out German energy policy and said that on Ukraine, “Berlin’s hesitation, its inaction, seriously calls into question the value of the alliance with Germany.”

“And we are not the only ones saying that,” he continued. “I am hearing this from quite a few other heads of government in Europe as well.”

Ukraine’s current pressure campaign on Germany comes after the latest meeting of the Ukraine Defense Contact Group, a coalition of dozens of nations organized by the Pentagon. Ukrainian officials, including Defense Minister Oleksii Reznikov, attended and briefed the group, according to Defense Secretary Lloyd Austin.

Germany has defended its record and called attention to its financial and military assistance to Ukraine. In diplomatic and policy circles, however, there is still much talk of Germany’s fading leadership within the European Union and in European security more broadly.

The question now is whether Ukraine’s most recent offensive will change Berlin’s calculus, spurring another major foreign policy shift.

“I understand that there is still a certain conservative thinking, there are certain fears, and there is a certain regret about the missed opportunities in the energy sector with the Russian Federation,” Podolyak said. “We all understand this, but there will be no return to the past. And now, in my opinion, is coming a critical moment for Germany when it is necessary to express its real position, the position of the European leader.”

Morris reported from Berlin, Rauhala from Brussels and Lamothe from Washington. The Washington Post’s Karen DeYoung in Washington contributed to this report.

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