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.

Sir Keir Starmer says western powers must avoid the mistakes of the past amid when striking a deal to end the war in Ukraine. Referring to the failed Minsk agreements signed in 2015, the prime minister told MPs in the House of Commons on Monday afternoon that “we cannot accept a weak deal” in securing peace.