SEOUL, Aug 15 (Reuters) - North Korean leader Kim Jong-il, who will visit Russia this month as part of Pyongyang's unprecedented recent diplomatic outreach, told Russian President Vladimir Putin on Thursday relations had entered a new phase.

The North's official KCNA news agency announced Kim's visit to Russia's far east, with which North Korea shares a tiny border, but gave no precise dates.

The Kremlin press service said the North Korean leader would visit the far east "in the last 10 days of August", but gave no further details.

Western diplomats in Seoul and Pyongyang have said the visit is likely to include stops in regional centre Khabarovsk and the port city of Vladivostok, where he is expected to meet Putin.

In a message marking the August 15 anniversary of the end of Japanese colonial rule on the Korean peninsula in 1945, Kim told Putin ties were developing steadily.

"I express belief that the bilateral relations of friendship and cooperation which have entered a new phase will expand and develop in various fields," Kim said, according to KCNA.

A year ago, Kim travelled by train across Russia and held talks with Putin in Moscow. Kim, like his father and state founder Kim Il-sung, does not like flying.

Putin has reinvigorated diplomatic ties with North Korea, which was a major ally of the Soviet Union but largely ignored by Moscow after communism in Russia collapsed in the early 1990s.

Putin told Kim in a Liberation Day message he was confident the North Korean leader's visit to Russia would help boost regional security as well as bilateral relations.

Political analysts say Russia's renewed interest is motivated by economic considerations as well as a desire to play a role in geopolitical stability on the Korean peninsula, where the United States is the South's main ally.

South Korea has also developed stronger ties with Moscow under Putin. One aim is to improve trade relations through future energy pipeline and rail links through North Korea.

North Korea has stepped up diplomatic activity in recent weeks, seemingly in tandem with tentative, piecemeal efforts to reform its creaking economy. It has held talks with South Korea this week and plans talks with Japan this month, too.

For Kim Jong-il, a trip to Russia would underscore his ties with Moscow before expected dialogue begins between North Korea and the United States. Nampa-Reuters 0951 150802 WEB story ENDS (NAMPA 150955)