Kyiv and Washington are expected to sign a framework deal over mineral resources on Friday that both sides tout as important, but whose most contentious element—military support to Ukraine—has yet to be negotiated.

The United States and Ukraine are trying to hammer out a natural resources agreement that would give Washington access to Kyiv’s untapped mineral riches in exchange for investments and what Ukraine hopes would be concrete security guarantees.

President Trump, who had insisted he wanted “payback” for past military aid to Kyiv, suggested President Volodymyr Zelensky would visit Washington this week to sign an agreement, which he called a “very big deal.