Donald Trump has abruptly cancelled bilateral talks with Vladimir Putin that were due to take place this weekend in Argentina, as tensions escalated between Moscow and Washington over the Russian seizure of three Ukrainian vessels.   

“Based on the fact that the ships and sailors have not been returned to Ukraine from Russia, I have decided it would be best for all parties concerned to cancel my previously scheduled meeting in Argentina with president Vladimir Putin,” Mr Trump wrote in a tweet as he flew to Buenos Aires for the G20 summit. “I look forward to a meaningful summit again as soon as this situation is resolved!,” he said.

The talks on the sidelines of the G20 event in Buenos Aires would have been the first formal sit-down meeting between the two leaders since their summit in Helsinki in July. The cancellation of the meeting will dash efforts to ease tensions as the US threatens new sanctions against Moscow and Mr Trump pledges to withdraw from a cold war-era agreement on  limiting nuclear missiles.