BEIJING - North Korean leader Kim Jong Il visited factories in northeastern China in Friday as he returns home from meetings in Russia where he pushed for renewing talks on his country's nuclear program.

The Yonhap News agency says Kim made a stop off in the city of Qiqihar in Heilongjiang province after crossing over from Russia the night before aboard his armored train. The North's official Korean Central News Agency reported that regional party officials greeted Kim's arrival but it did not mention his Friday agenda.

State media in both countries are typically secretive about his activities and travels while they are ongoing, and Yonhap said no other details about the factory visits were available. His last trip to China earlier this year focused on manufacturing and economic sites as China encourages its impoverished ally to reform its economy.

China is the North's most important diplomatic ally and a key source of food and economic aid.

Kim agreed in Russia to impose a nuclear test and production moratorium and return to international talks on Pyongyang's atomic program without preconditions.

Faced with deepening sanctions and economic woes, North Korea wants the six-nation talks to resume.

Washington and Seoul have been wary of the North's calls for renewed talks, calling first for an improvement in dismal ties between the Koreas and for a sincere sign from the North that it will abide by past commitments it has made in previous rounds of talks.

North Korea is believed to have enough weaponized plutonium for at least six atomic bombs, and is believed to be working toward mounting a nuclear bomb on a long-range missile.

Last year, it unveiled a uranium enrichment facility that could give it a second way to make nuclear weapons.