South Korean intelligence agency believes Russian Defense Minister Sergei Shoigu proposed a joint military drill with North Korea and China during his visit to Pyongyang about a month ago.

It was likely Shoigu who suggested a three-way maritime drill when he met with North Korean leader Kim Jong-un, National Intelligence Service Director Kim Kyou-hyun was quoted by ruling People Power Party Rep. Yoo Sang-bum as telling the National Assembly intelligence committee on Monday.

The Russian defense minister was invited to attend Pyongyang's celebrations of the 70th anniversary of the Korean War armistice July 25-27.

The assessment by the South Korean intelligence agency follows Russian Ambassador to North Korea Alexander Matsegora's interview with Moscow's state-run news agency over the weekend, in which he spoke approvingly of including North Korea in combined military exercises with Russia and China.

The recent military provocations by North Korea were interpreted to be in response to the Ulchi Freedom Shield exercise, the South Korean intelligence director told the Assembly committee, according to Yoo.

North Korea seems to be preparing a series of short-term operations using both conventional and tactical nuclear weapons based on recent trends in its missile tests.