President Trump joined a call Thursday with Ukrainian President Volodymyr Zelensky and world leaders during which he urged Europe to stop purchasing Russian oil as a way to undercut Moscow's war in Ukraine.

French President Emmanuel Macron and Zelensky met in France, while roughly 20 other leaders joined the meeting virtually to discuss efforts to end the war in Ukraine, which has been raging since Russian forces invaded in February 2022.

"President Trump emphasized that Europe must stop purchasing Russian oil that is funding the war — as Russia received €1.1 billion [$1.28 billion] in fuel sales from the EU in one year," a White House official said in a statement. "The president also emphasized that European leaders must place economic pressure on China for funding Russia’s war efforts.”

The call took place as progress has appeared to stall on efforts by Trump and others to end the war in Ukraine. The president has sought to arrange a meeting between Zelensky and Russian President Vladimir Putin, but there has been little progress on getting the two leaders together.

Trump has bristled at the suggestion that he has not taken action against Russia as it continues to bombard Ukraine with drone strikes, pointing to tariffs he imposed on India over its purchase of Russian oil and gas.

Trump told CBS News in an interview late Wednesday that he remained optimistic there would be a conclusion to the war, even if it was not imminent.

"Something is going to happen, but they are not ready yet," the president said. "But something is going to happen. We are going to get it done."

Leaders from Germany, the United Kingdom, Italy, Japan and several other nations joined Thursday's call, members of what is dubbed the "Coalition of the Willing."

Zelensky said following the meeting that the group discussed security guarantees for Ukraine and additional sanctions on Russia.

"We share the same view that Russia is making every effort to drag out the negotiation process and prolong the war," Zelensky posted on social platform X. "Support for Ukraine must be increased and pressure on Russia must be intensified. Preparations for the 19th EU sanctions package are underway. Japan is also working on sanctions measures."

Putin has in recent days met with Chinese President Xi Jinping, Indian Prime Minister Narendra Modi and North Korean leader Kim Jong Un, raising concerns that those nations are forging a close partnership to counter the U.S. and Europe.