SEOUL - CHINA and South Korea on Tuesday reaffirmed their resolve to press for North Korea's nuclear disarmament as visiting President Hu Jintao met Prime Minister Han Seung Soo, Mr Han's office said.

Mr Hu and Mr Han also agreed to strengthen energy and economic cooperation, the office said in a statement.

On the first day of the Chinese leader's visit on Monday, the two countries agreed on a variety of measures to strengthen relations established 16 years ago between the former Cold War adversaries.

Mr Hu and President Lee Myung Bak called for regular dialogue between top diplomats and defence officials. They reconfirmed their commitment to persuade North Korea to scrap its nuclear weapons through six-nation negotiations chaired by China.

And the presidents agreed to increase their annual trade volume to US$200 billion (S$284 billion) by 2010, from US$145 billion last year.

China since 2003 has hosted six-nation nuclear negotiations which also involve the two Koreas, the United States, Russia and Japan.

Under an aid-for-disarmament deal reached last year, the North is disabling its atomic complex and has handed over details of its plutonium-based nuclear programme.

But it cannot agree with the United States on ways to verify the declaration.

Mr Hu and Mr Han 'exchanged views on the global energy price increase and its effect on the global economy and agreed to strengthen cooperation on energy buying and saving,' Mr Han's office said. No details were given.

They then attended the signing of a memorandum of understanding on suppporting each other's upcoming Expo events. China and South Korea will host industrial expositions in Shanghai in 2010 and in Yeosu in 2012.

Earlier on Tuesday, Mr Lee showed Mr Hu Seoul Forest, one of his most prized environmental projects when he was the capital's mayor.

They discussed closer cooperation in 'green growth' in front of about 250 youth representatives from both countries.

The 114ha riverside public park was opened in 2005.

The two leaders exchanged views on environmentally friendly urban development, the use of clean energy and green growth, and planted a commemorative pine.

Mr Hu was to have lunch with business leaders and leave on Tuesday afternoon for a meeting of the Shanghai Cooperation Organisation in Tajikistan.