Talks between Russia and Ukraine are continuing in an attempt to agree terms for a ceasefire.
Ukraine is understood to be rejecting proposals by Russia that it become a neutral state.
Ukraine has stated that it will not seek to join NATO, one of the demands made by Russia.
Russian Foreign Minister Sergey Lavrov says an agreement is close, however the talks could drag on for weeks, while Ukraine has made cautious positive statements on peace talks.
It said it is willing to negotiate to end the war, but will not surrender or accept Russian ultimatums.
Ukrainian President Volodymyr Zelensky is to address the US Joint Houses of Congress today (Wednesday).
A major US aid package to be announced today is expected to include more anti-tank and anti-aircraft missiles as missile and artillery attacks continue across Ukraine.
The conflict has already created more than three million refugees as Ukrainians flee the country.
The UN Development Programme says nine out of 10 Ukrainians could face poverty and extreme economic vulnerability if the war drags on over the next year, wiping out two decades of economic gains.
