The United States and China have agreed to increase cooperation on nuclear non-proliferation and counter-terrorism efforts.

U.S. Energy Secretary Spencer Abraham and Zhang Huazhu, head of China's Atomic Energy Authority, signed the agreement at the end of Mr. Abraham's visit to Beijing Monday.

U.S. Embassy officials say the document is a statement of intent to boost cooperation in several areas, including strengthening export controls and international nuclear safeguards.

The signing of the agreement came two days after an unofficial U.S. delegation visited North Korea. The tour included a visit to the Yongbyon nuclear facility, the main component of North Korea's nuclear weapons program. Pyongyang says it showed elements of its nuclear deterrent force to the delegation.

China has been working to broker talks to end an international standoff over North Korea's nuclear weapons programs, which violate several international accords.

During his visit to Beijing, the U.S. energy secretary signed another agreement, saying the two nations will work together to develop clean energy technologies ahead of the Beijing Olympics in 2008.

The agreement includes establishing 11 teams that will work to make sure the Beijing Games efficiently use water and energy.

China has pledged to hold what officials have termed as "Green Olympics." In its bid for the games, Beijing promised to cut energy consumption and clean up the environment. Beijing is highly polluted, especially its air.

Officials said China and the United States are among the world's top consumers of energy.