Russian Defense Minister Andrei Belousov is in North Korea for a previously unannounced visit, the Russian Defense Ministry said Friday.

Belousov is in Pyongyang to hold talks with North Korean “military and military-political officials,” the ministry said.

The Russian defense chief was welcomed in Pyongyang by his North Korean counterpart, No Kwang Chol, backed by a military band.

Belousov hailed “expanding” ties with North Korea. “Friendly ties between Russia and North Korea are actively expanding in all areas, including military cooperation,” he said, according to Russian news agencies.

Russia and North Korea have strengthened their military ties since Moscow launched its full-scale invasion of Ukraine in February 2022.

The two countries signed a strategic partnership treaty in June which was recently ratified. The treaty provides for mutual military assistance in case of an attack and cooperation in the face of Western sanctions.

The United States and South Korea have accused Pyongyang of sending more than 10,000 soldiers to help Russia fight Ukraine, with experts saying leader Kim Jong Un was eager to gain advanced technology and battle experience in return for his troops.