President Donald Trump said Wednesday that Ukrainian leader Volodymyr Zelenskyy will visit the White House on Friday to sign a long-sought minerals deal that will closely tie the two countries together for years to come.

The U.S. and Ukraine are near a deal to hand valuable mineral rights to the U.S., an agreement the Trump administration has sought as compensation for military aid to fight off Russia’s invasion, people familiar with the matter said.

President Trump said that Ukraine’s president may soon visit the White House to sign a deal, though how it ties in to efforts to end the Russian invasion and guarantee Ukraine’s security is unclear.