Kim Jong Un will visit Russia “in the coming days,” the Kremlin announced Monday following speculation about an upcoming visit by the North Korean leader.

Kim’s visit will take place “at the invitation of Russian President Vladimir Putin,” the statement said.

Last week, a U.S. official said the North Korean leader was expected to travel to Russia by the end of September, as an increasingly isolated Moscow is looking to buy artillery ammunition from North Korea for its invasion of Ukraine.

In a recent letter to Kim, Putin called for the two countries to “strengthen … bilateral ties on all fronts.”