Other lower level meetings planned for this week underscore the massive task ahead for European allies as they weigh plans for sending a peacekeeping force to Ukraine.

Polish Prime Minister Donald Tusk has said he is not in favour of potential talks between President Volodymyr Zelenskyy and Russian ruler Vladimir Putin being held in Hungary, given that the Budapest Memorandum was signed there in 1994.

Russia peace talks in Budapest, a city tied to the broken 1994 security pact, with Trump set to join if the summit happens