In a declaration, President Vladimir Putin and his South Korean counterpart, Roh Moo-hyun, stressed their commitment to the non-nuclear status of the Korean Peninsula and to six-nation talks on North Korea's nuclear program.

"Our country has consistently called for a non-nuclear status on the Korean Peninsula and for the continuation of the six-nation negotiating process," Putin told reporters after his summit talks with Roh at the Kremlin.

The Russian leader also sought to preempt concerns that development of closer cooperation between Moscow and Seoul would take place to the detriment of the United States or any other country in the region.

"Cooperation between the Russian Federation and the Republic of Korea is aimed at strengthening peace and cooperation in northeast Asia," Putin said.

"Our common work is not aimed against someone. It is aimed at strengthening security and boosting cooperation, not only between our two countries but in all the countries of the region," he added.

The joint declaration called for stronger measures to fight terrorism and said both sides agreed "proliferation of weapons of mass destruction and the means for their delivery represent a threat to international peace and security".

Putin is among the few heads of state to have met personally with North Korea's reclusive Stalinist leader, Kim Jong-Il, and Roh insisted several times that Russia had a "special" role in the six-party negotiation process.

"Moscow may be located on the European continent but Russia plays an important role in northeast Asia," Roh said before the meeting. "We thank Russia for this role in bringing peace and stability to the Korean Peninsula."

The six-party process involves, in addition to the two Koreas, the United States, China, Russia and Japan.

Washington has pushed for a new round of six-party talks to begin this month but Pyongyang has so far balked at attending, recently saying it would not do so until South Korea's nuclear status had been clarified.

South Korea recently disclosed its own nuclear experiments to enrich uranium four years ago and to extract a small amount of plutonium in the 1980s, and admitted it should have reported this to international monitors.

If the words of the summit centered on security issues, the deeds were focused squarely on building economic and business ties between energy-rich Russia and South Korea, the world's fourth largest oil importer.

Putin and Roh, along with top business leaders from both countries, signed a slew of trade and investment contracts or preliminary agreements in a number of sectors that the Russian leader valued at over four billion dollars.

One of the deals included a project for investment of around 2.6 billion dollars from the South Korean firm LG International Corp. in a petrochemical and oil refining complex in Tatarstan, according to South Korean officials.

Under the terms of another deal, South Korea's industrial giant Samsung said it would invest 500 million dollars in a 10-year project for modernizing an oil refinery in the Far East Russian city of Khabarovsk, Russian officials said.

Under the terms of that contract, 80 percent of the oil refined at the Khabarovsk facility will remain in Russia while the remaining 20 percent would be exported to South Korea, China and Japan.

In their declaration, the two leaders pledged to "activate" work on linking Russia's trans-Siberian railway to a trans-Korean system that passes through North Korea.

The two sides also signed an accord for Russia to train and launch South Korea's first cosmonaut into space, and for Russia to provide assistance to South Korea for the development of its own space program and launch facilities.

During the Kremlin talks, Roh invited his Russian counterpart to make an official visit to South Korea.

Russia also secured South Korea's agreement for Russian accession to the World Trade Organization (WTO), the RIA-Novosti news agency reported.