Ukraine tensions: Putin tells Biden new sanctions could rupture ties

Russia's Vladimir Putin has warned his US counterpart Joe Biden that imposing new sanctions over Ukraine could lead to a complete breakdown in relations.

In a phone call late on Thursday, the Russian president said such sanctions would be a "colossal mistake".

Mr Biden, meanwhile, told Mr Putin that the US and its allies would respond decisively to any invasion of Ukraine.

The call, requested by Russia, was the pair's second such conversation this month and lasted for almost an hour.