British Prime Minister Keir Starmer’s exhortation comes two days after U.S. backing of Ukraine appeared in jeopardy when President Donald Trump lashed out at Ukrainian President Volodymyr Zelenskyy.

President Volodymyr Zelenskyy arrived in the U.K. on Saturday, directly after his meeting with President Donald Trump and Vice President JD Vance in Washington, D.C.

The meeting has been overshadowed by the extraordinary scolding of Ukrainian President Volodymyr by President Trump at the White House.

Leaders from around 15 European countries began arriving in London on Sunday for an informal summit on Ukraine.

This summit was in many ways an attempt by Europe to take some ownership of the diplomacy. In recent weeks, efforts to end fighting in Ukraine have been led by Trump speaking to Russian's President Vladimir Putin and at his Ukrainian counterpart Volodymyr Zelensky.

The meeting is taking place after a blazing row between Donald Trump and Volodymyr Zelensky in the Oval Office

Keir Starmer has been gathering European leaders and trying to build a coalition of countries to accelerate stopping the war in Ukraine. | ITV National News

Justin Trudeau, the prime minister of Canada, has just arrived at Lancaster House for Sir Keir Starmer's international summit on defence and security. Ursula von der Leyen, the president of the European Commission, has just arrived at Lancaster House.

March 2 (UPI) --After President Donald Trump's heated exchange with Volodymyr Zelensky at the White House last week, the Ukrainian president met with a summit of European leaders at Lancaster ...

Britain's Prime Minister Keir Starmer, front center, hosts the European leaders' summit to discuss Ukraine, at Lancaster House ... European Commission President Ursula von der Leyen, European ...