BEIJING -- Marine Gen. Peter Pace, chairman of the US Joint Chiefs of Staff, arrived in Beijing on Thursday for a four-day visit, the latest sign of the warming ties between the two armed forces.

Invited by Chief of the General Staff of the People's Liberation Army(PLA) Liang Guanglie, Pace is the first high-ranking US military officer to visit China this year.

This is also Pace's first China visit since he was sworn in as Chairman of the Joint Chiefs of Staff in 2005.

During Pace's stay in Beijing, he is scheduled to meet with Guo Boxiong and Cao Gangchuan, who are both vice chairpersons of China's Central Military Commission (CMC), China's top military authority.

Pace will also hold talks with Liang Guanglie on a wide ranging of issues. He will also hold a seminar with researchers with the PLA Military Science Academy.

In addition, the four-day visit will also take Pace to China's military areas and institutions.

Pace will meet with the leaders of Military Areas of Shenyang and Nanjing.

Pace's visit is part of the growing high-level visits between Chinese and US armed forces over the past years.

Guo Boxiong paid a week-long visit last July at the invitation of US Defense Secretary Donald Rumsfeld. He was the highest-ranking Chinese military officer to visit the United States since 2001.

William Fallon, Commander of US forces in the Pacific, came last May and August. He invited a Chinese delegation to observe a US military exercise in Guam last June, the first invitation of its kind extended by the United States.

The defense departments of the two countries restored a series of consultation mechanisms on maritime security, humanitarian disaster relief and military environmental protection.

A breakthrough in China-US military ties was the first-ever China-US search-and-rescue exercise last year.

Yet analysts said there remain some "obstacles" preventing China-US military ties from going forward, which include the Taiwan issue.

In late February, the U.S. Department of Defense announced that it planned to sell Taiwan over 400 missiles worth 421 million US dollars.The proposed sale will include Advanced Medium Range Air-to-Air missiles, Maverick missiles, as well as spare parts and maintenance equipment.

The US congress passed some bills limiting military exchanges with China, as represented by the 2000 Fiscal Year Defense Authorization Act.