A U.S. official said Monday that North Korean leader Kim Jong Un may travel to Russia soon to meet with President Vladimir Putin as the Kremlin tries to acquire military equipment for use in its war in Ukraine.

The official, who was not authorized to address the matter publicly and spoke to The Associated Press on condition of anonymity, said the U.S. expects Kim will make the trip within the month. The official said the U.S. isn’t sure exactly where or when the meeting would take place, but the Pacific port city of Vladivostok would be a likely possibility given its relative proximity to North Korea.

National Security Council spokeswoman Adrienne Watson noted Monday that Russian Defense Minister Sergei Shoigu traveled to Pyongyang last month and tried to persuade North Korea to sell artillery ammunition to Russia.