Sen. James E. Risch, the top Republican on the Foreign Relations Committee, is halting a $735 million U.S. arms sale to Hungary as punishment for the country’s refusal to approve NATO membership for Sweden, a rare move aimed at pressuring Budapest into greenlighting the military alliance’s expansion ahead of a major summit next month.

In a statement to The Washington Post, Risch (Idaho) said Hungary must allow Sweden into NATO if it wants the arms package, which includes 24 HIMARS rocket launcher batteries, and more than 100 rockets and pods along with associated parts and support.

The decision to slam the brakes on new arms sales to Budapest demonstrates the growing anger toward Hungary by NATO backers like Risch, who rarely holds up arms sales to countries in any part of the world.

“For some time now, I have directly expressed my concerns to the Hungarian government regarding its refusal to move forward a vote for Sweden to join NATO,” he said.

“The fact that it is now June and still not done, I decided that the sale of new U.S. military equipment to Hungary will be on hold,” he added.

All significant arms sales require the chair and ranking members of the Senate and House foreign affairs committees to give clearance and approval before the sale is publicly noticed by the State Department. Risch’s objection prevents the State Department from being able to move forward in the sales process.

A State Department spokesperson declined to comment on the matter, saying the department does not comment on “pending arms sales.”

A spokesman for the Hungarian government did not respond to a request for comment.

Risch’s maneuvering comes as NATO Secretary General Jens Stoltenberg visited the White House on Tuesday in an effort to coordinate strategies for the NATO summit this summer in Lithuania, where President Biden and Stoltenberg hope to announce progress on Sweden’s bid to join the military alliance.

Sweden and Finland’s decision to apply for NATO membership has been widely viewed as a blow to Russian President Vladimir Putin, who justified his invasion of Ukraine by underscoring the threat the military alliance poses to his country.

U.S. officials say Putin did not anticipate the West would hold together in support of Ukraine as it has, but they worry that the decision by Hungary and Turkey to delay ratification for Sweden’s bid, which requires the support of all of the alliance’s existing members, risks exposing it as divided and ineffective.

The U.S. ambassador to Hungary, David Pressman, said “The United States will continue to work tirelessly towards closer collaboration with our ally. However, we have real concerns about strategic decisions Hungary is making - and those concerns are shared broadly.”

Relations between the United States and Hungary have become increasingly combative in recent months, as Budapest delays and complicates the Western response to Russia’s war in Ukraine.

As a veto-wielding member of both NATO and the 27-member European Union, Hungary holds outsize international influence. Prime Minister Viktor Orban has blocked European defense funding for Ukraine, stymied sanctions packages and deepened energy ties to Russia, leading to accusations that Budapest is working as Putin’s Trojan horse.

Hungary’s continued blocking of Sweden’s NATO membership bid has caused exasperation among allies. Speaking in Qatar last month, Orban said relations between Hungary and Sweden must improve before Stockholm’s bid for membership is improved.

Washington has also expressed alarm over Budapest’s willingness to expand and deepen ties with Moscow, taking a harder line in April when the U.S. Treasury imposed sanctions on officials at the Hungary-based International Investment Bank, an unusual move against an entity linked to an ally.

At the time, Pressman, the U.S. ambassador, expressed exasperation that the Hungarian government had “dismissed the concerns of the United States government” regarding the bank that Washington said was being used as a base for Russian espionage.

Orban struck a more conciliatory tone following the public censure describing the United States as a “friend and ally.”

Risch’s move against the Orban government stands in contrast to the embrace the far-right prime minister has received from some U.S. conservatives, in particular, those who hosted him at last year’s Conservative Political Action Conference. At the event, Orban received loud applause as he designated liberals as a common enemy. “They hate me and slander me and my country, as they hate you and slander you for the America you stand for,” he said.

Hungary has not publicly announced its request to purchase HIMARS, but Hungarian newspaper Szabad Europa reported in January that Budapest was mulling a purchase, citing defense ministry officials. The rocket systems, credited with elevating Ukraine’s ability to thwart Russia’s advance, are already in possession or on order for many of the countries on NATO’s eastern flank. Poland took its first delivery of M142 HIMARS last month and is aiming to buy around 500 more.

Morris reported from Berlin.

previous coverage

• NATO defense chiefs plan to upgrade ties with Ukraine