Britain"s prime minister, Keir Starmer, has called on the US to provide a "backstop" to deter Russia from attacking Ukraine again after meeting with European leaders for emergency talks on the war. Starmer said Donald Trump’s comments asking Europe to step up "should not come as a surprise", and repeated that he is prepared to consider committing British forces on the ground alongside others. Ukraine will not accept a Saudi-talks peace deal, says Zelenskyy