BRUSSELS/WASHINGTON (Reuters) -U.S. President Joe Biden will meet NATO and European Union leaders in Brussels next week for a summit to discuss Russia’s invasion of Ukraine with no sign of Moscow backing down.

NATO Secretary General Jens Stoltenberg announced the March 24 meeting in a Twitter post on Tuesday and the White House confirmed Biden would attend, as well as a European Council Summit the same day.

The official announcement of the meeting at NATO headquarters, which was first reported by Reuters on Monday, was made two days after Russian missiles hit a Ukrainian base near the border with NATO member Poland, an attack that brought the conflict to the doorstep of the Western alliance.

NATO bolstered countries on its eastern flank with additional troops in the months before the Feb. 24 Russian invasion.

Biden, whose administration has been in close contact with its NATO allies and others over the war, aims to cement the cohesiveness, White House spokesperson Jen Psaki said.

“His goal is to meet in person face-to-face and talk about and assess where we are at this point in the conflict,” she said. “We’ve been incredibly aligned to date. That doesn’t happen by accident.”

Polish Foreign Minister Zbigniew Rau was quoted as saying that a visit by Biden to Poland “seems very much probable” but the White House declined to comment. Psaki said details of the trip were still being worked out.

NATO defense ministers will also meet on Wednesday in what Stoltenberg called “a defining moment for our security.”

“I think it’s a very important trip that the President is making,” Deputy Secretary of State Wendy Sherman said. She called U.S. solidarity with NATO and the European Union unprecedented, and contrasted it with Russia’s less-clear alliance with China.

“This is one of the great advantages we have a vis-a-vis Russia, who has very few, if any, allies or partners,” Sherman said in an interview with CNN. “And I think if in fact the PRC is a partner is a partner of just transactional relationship, not of true interests.”

Ursula von der Leyen, president of the EU Commission, said she was glad to continue discussions with Biden in person. “Transatlantic unity and coordination remain crucial for ramping up pressure on the Kremlin to stop this unjustified war,” she wrote on Twitter.

Zelenskiy has been pleading for NATO to impose a no-fly zone to protect his country from Russian aerial bombardment, but the alliance is wary of any step that might draw it into direct conflict with fellow nuclear-armed power Russia.

The Ukrainian leader will likely state his case again when he addresses the U.S. Congress on Wednesday. He spoke to Canadian lawmakers on Tuesday and to the British Parliament last week.

(Reporting by Marine Strauss in Brussels and Jarrett Renshaw and Doina Chiacu in Washington; Editing by Edmund Blair, Nick Macfie and Grant McCool)

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