SEOUL (Reuters) - A North Korean elite military training delegation has left for a visit to Russia, the North's state media said on Tuesday, the first military exchange between the two countries since their leaders signed a pact pledging closer military cooperation.

The president of the Kim Il Sung Military University, Kim Geum Chol, is leading the delegation of military training officials and departed by plane on Monday, KCNA state news agency reported.

It gave no other details including the purpose of the visit and where in Russia they were visiting.

Named after the state founder, the university is a training ground for elite military officers, and the country's leader, Kim Jong Un, attended after studying in Switzerland while being groomed as the country's third leader.

The military university delegation marks the latest North Korean visit to Russia as they exchanged a record number of high-level officials in the past year, including Russian President Vladimir Putin's visit to Pyongyang in June.

At their summit, Putin and Kim signed a treaty on the "Comprehensive Strategic Partnership" that included a mutual defence agreement which Kim said amounted to an alliance.

The highly public development of the two countries' military ties worry officials in Seoul and Washington who point to evidence of weapons shipments by the North to Russia for use against Ukraine and believe Pyongyang may be receiving unknown assistance from Moscow.

The two countries deny any arms transactions.

South Korean President Yoon Suk Yeol, who will be attending a NATO summit this week in Washington, warned Moscow of negative fallout from its friendship with Pyongyang on what had been an active economic relationship between the two countries.

(Reporting by Jack Kim; Editing by Michael Perry)