Top American and Russian diplomats have agreed to keep talking despite the stand-off over Ukraine.
It comes amid fears Russia will invade Ukraine after Moscow massed tens of thousands of troops at the border.
The UK has given Ukraine supplies – the country's deputy defence minister Anatolii Petrenko welcomed British military personnel and their delivery of defensive weapons systems.
It is reported some 2000 anti-tank missile launchers have been delivered, along with expert troops to provide training.
The diplomatic intentions are clear – Russia wants assurances that NATO will not sign-up new members like Ukraine, while the US and NATO want assurances that Russia will not invade Ukraine.
A diplomatic summit in Switzerland, aimed at reducing tensions, did not bring about any change.
US secretary of state Antony Blinken and Russian foreign minister Sergey Lavrov met for about 90 minutes in Geneva at what the American diplomat said was a "critical moment".
Mr Blinken told Mr Lavrov the US would give Russia written responses to Moscow's proposals next week and suggested the two would likely meet again shortly after that – offering some hope that any invasion would be delayed for at least a few more days.
The US secretary of state said America and its allies remain resolute in rejecting Russia's most important demands, which were reiterated on Friday.
Watch: What does Russia want from NATO?
Mr Blinken said Mr Lavrov repeated Russia's insistence that it has no plans to invade Ukraine, but the US and its allies remain unconvinced.
He also said Moscow should remove its troops from the border if it wishes to prove its point.
Mr Lavrov, meanwhile, called the talks "constructive and useful" but declined to characterise the US pledge.
The US and its allies say Russian president Vladimir Putin knows his demands are non-starters, adding that they are open to less dramatic moves.
Mr Blinken said the US would be open to a meeting between Mr Putin and US president Joe Biden if it would be "useful and productive".