CNN —

The Biden administration is moving toward lifting a de facto ban on American military contractors deploying to Ukraine, four US officials familiar with the matter told CNN, to help the country’s military maintain and repair US-provided weapons systems.

The change would mark another significant shift in the Biden administration’s Ukraine policy, as the US looks for ways to give Ukraine’s military an upper hand against Russia.

The policy is still being worked on by administration officials and has not received final sign-off yet from President Joe Biden, officials said.