Luo said China and the United States had effectively co-operated in trade, fighting against terrorism, law enforcement, nuclear non-proliferation, controlling bird flu, the nuclear issues on the Korean Peninsula and in Iran, and reconstruction in Iraq and Afghanistan.

"We hope to make substantial achievements in extradition, fighting terrorism, Olympic Games security and illegal emigration," he said.

He also mentioned that Chinese President Hu Jintao's impending visit to the United States was the top priority this year with respect to Sino-US relations.

Yang Jiechi, a former Chinese ambassador to the US, said that frequent ministry-level visits between the two countries, including the recent visit of US Commerce Secretary Carlos Gutierrez and the current visit of Chinese Vice-Premier Wu Yi, would enhance mutual understanding and are favourable to Hu's visit.

Chertoff's Asia trip, which also took him to Singapore, Tokyo and Hong Kong, focused on ports and aviation security, with Washington worried that nuclear bombs or radioactive material could be smuggled into its borders in shipping containers.

China and the United States were also near an agreement on air security, Chertoff said, without giving details.

A container security initiative has already begun at some Chinese ports and the two countries are working to deepen relations between their customs officials.

"It's critical for us to have a relationship with China that elevates the security of the movement of those containers, but in a way that doesn't interfere with the process of rapidly moving cargo to the United States," Chertoff said.