Ukraine is poised to sign a landmark mineral resources agreement with the United States in Washington on Wednesday, according to two senior Ukrainian officials who spoke on condition of anonymity because they weren't authorised to discuss the matter publicly.

Economy Minister Yulia Svyrydenko is currently in Washington for the final coordination of the agreement's technical details, the sources said.

It wasn't immediately clear whether the Trump administration, which has pressed for the agreement to be signed, was also ready to ink the deal.

Trump has said that he wants Ukraine's rare earth elements as a condition of further support in its more than three-year war with Russia.

Ukraine has deposits of titanium, which is used for making aircraft wings and other aerospace manufacturing. It also has lithium, key to several current battery technologies, and uranium, used for nuclear power, medical equipment and weapons. On top of that, it has graphite and manganese, both used in batteries for electric vehicles