His trips to Britain, Germany, France and Italy demonstrated the shifting political landscape when it comes to supporting Kyiv, as concerns grow about U.S. backing as the presidential election looms.
President Volodymyr Zelensky of Ukraine has been promised billions of dollars in new military aid during a whirlwind tour of European allies that reflects a striking shift in the political landscape, as Europe takes a more central role in arming Ukraine for its anticipated counteroffensive to drive Russia from its territory.
Mr. Zelensky’s four-country tour began in Italy on Saturday and ended in Britain on Monday, when Prime Minister Rishi Sunak pledged to provide a major package of air-defense missiles and attack drones. That was in addition to Britain’s recent delivery of long-range cruise missiles. And it followed Germany’s pledge to give Ukraine a nearly $3 billion package of weapons, as well as less concrete promises of additional weapons from France and Italy.
Europe’s show of support for Ukraine, analysts said, underscores that the war is in a pivotal phase, with Ukrainian forces massing for a counteroffensive that could set the terms for any future negotiation with Russia. It also reflects a recognition that support for Ukraine in the United States, still by far the largest supplier of weapons, is likely to come under pressure.
Mr. Zelensky is concerned that as the American presidential race heats up, President Biden will be less able to lead diplomatic efforts, German and Ukrainian officials said. Should a Republican win the White House, officials worry there will be a collapse in leadership among Western allies.
“This is a crucial moment in Ukraine’s resistance to a terrible war of aggression they did not choose or provoke,” Mr. Sunak said in a statement, as he welcomed Mr. Zelensky at Chequers, the British leader’s country residence outside London.
Mr. Zelensky, who hugged Mr. Sunak after climbing out of a helicopter, described the meetings as “substantive negotiations” and referred to Mr. Sunak in a post on Twitter as “my friend Rishi.” The two met in a room used by Winston Churchill to write his rally-the-nation radio broadcasts during World War II.
Mr. Zelensky held similarly warm meetings with Chancellor Olaf Scholz of Germany in Berlin and President Emmanuel Macron of France in Paris, both on Sunday; and with Prime Minister Giorgia Meloni of Italy in Rome, where he also met Pope Francis, on Saturday. From his visits, Mr. Zelensky emerged with at least the promise of more weapons.
The new long-range missiles, attack drones and tanks and other armored vehicles secured from allies in recent days will fulfill many, but not all, of the demands for weapons that Ukraine has said it needs for a counteroffensive.
“The trajectory across Europe is to do more,” said Malcolm Chalmers, the deputy director general of the Royal United Services Institute, a research group in London. “That is partly about the evolution of European politics. It’s also driven by the expectations that the next few months are critical, and things could go either way.”
“The prospect of faltering American commitment as we approach the election is at the back of people’s minds,” Mr. Chalmers added. “That has led to the desire to get Ukraine to the best possible position before negotiations.”
White House officials have said privately that they remain confident they have bipartisan support in Congress to continue helping Ukraine in the near term, but they have not sought additional financial aid since Republicans took over the House and, so, have not tested that assumption.
Taken together, military analysts said, the European reinforcements make it highly likely that Ukrainian troops will soon strike back at Russian forces that control the country’s south, setting off what could be one of the bloodiest stretches of the 15-month war. Mr. Zelensky had warned that without more weapons, the counteroffensive could be delayed.
Germany was the first to answer his call: Its commitment included 30 additional Leopard tanks, 20 armored fighting vehicles, 16 air-defense systems, more than 200 drones and a slew of other arms and ammunition.
The Leopards and armored fighting vehicles could be useful in reclaiming territory, since the grassy steppe in Ukraine’s south is suited “for tank or maneuver warfare,” said Jacob Funk Kirkegaard, a former Danish army intelligence officer who is now a senior fellow at the German Marshall Fund in Brussels.
Britain’s missiles and drones, he added, could be used to attack Russian bases in Crimea, the Black Sea peninsula that Moscow seized after a disputed referendum in 2014.
Russia’s Defense Ministry claims that the long-range missile, known as Storm Shadow, has already been fired by forces in eastern Ukraine, injuring six civilians on Saturday. The claim could not be independently verified, and there was no comment from Britain.
The Kremlin expressed anger at Britain’s pledge. “We take an extremely negative view of it,” said the Kremlin spokesman, Dmitri S. Peskov, according to the Russian state news agency TASS. But he added that the weapons would “not have any significant impact” on the war.
The United States has resisted sending long-range missiles to Ukraine, in part to avoid escalating the conflict with weapons that could reach into Russian territory. That is also one reason the Biden administration has not acceded to Ukraine’s requests for American-made F-16 fighter jets.
American officials have said, however, they will not block other states from sending their own weapons to Ukraine. And analysts said Britain would not have given the long-range missiles without Washington’s tacit approval.
Mr. Sunak promised to start training Ukrainian fighter pilots on F-16s this summer. Mr. Macron also said in a televised interview on Monday that France and other European countries had “opened the door to training pilots” and that “training can start right away.” He added that “discussions are underway with the Americans.”
Europe’s increased pledges, analysts said, reflect a growing confidence that Ukraine’s troops could make decisive breakthroughs with its counteroffensive. Driving Russia out of Ukrainian territory would greatly increase Mr. Zelensky’s leverage in any negotiation with President Vladimir V. Putin of Russia.
“We wouldn’t be committing this amount of weapons to Ukraine at this point if the thinking was that it was not likely that they would succeed,” Mr. Kirkegaard said. “Nothing is certain, but we in the West seem to be increasingly bullish on Ukraine.”
In February, on his first visit to Western Europe after the war broke out, Mr. Zelensky visited London, where he appealed for combat aircraft before traveling to Paris for a meeting with Mr. Macron and Mr. Scholz. This time, Britain was Mr. Zelensky’s final stop.
With its aggressive approach, Britain has often acted as a catalyst for more reluctant Western countries to supply Ukraine with heavier weapons. Its decision to send a squadron of Challenger 2 battle tanks, for example, foreshadowed decisions by Germany and the United States to send more sophisticated tanks.
Britain also provided about $2.8 billion in military aid to Ukraine in 2022, making it the country’s largest backer after the United States and Germany.
European and Ukrainian officials said Mr. Zelensky was also privately pushing for a greater European role on the diplomatic stage. Ukraine is wary of countries with close relations to Russia, like China and Brazil, drawing up peace plans or acting as mediators.
Mr. Zelensky hopes to get allies like Germany more involved, according to a Ukrainian official who spoke on the condition of anonymity because of the sensitivity of the matter.
Mr. Macron, who has tried to position himself as a key diplomatic player in future peace talks, pressed China’s top leader, Xi Jinping, last month to use his close relationship with Moscow to help start negotiations.
China later announced it would send Li Hui, its special representative for Eurasian affairs, to Ukraine after a phone call between Mr. Xi and Mr. Zelensky. Mr. Li was to begin his trip on Monday to Ukraine and Russia in an attempt to help negotiate an end to the war.
Reporting was contributed by Lara Jakes in Rome, Erika Solomon and Christopher F. Schuetze in Berlin, Peter Baker in Washington, Constant Méheut in Paris and Vivian Wang in Beijing.