Portuguese President Jorge Sampaio left Lisbon on Monday night for China on state visit at the invitation of Chinese President Hu Jintao.

The main purpose of his 8-day trip is to infuse new vigor into bilateral economic ties, expanding cooperation in trade, investment and tourism, Sampaio told Xinhua in an interview before departure.

Sampaio will visit Beijing, Shanghai and Macao during his trip, accompanied by Economic Activities and Labor Minister Alvaro Barreto, Foreign Affairs and Portuguese Communities Minister Antonio Monteiro, and a delegation of more than 100 entrepreneurs.

The visit, on the occasion of the 25th anniversary of the establishment of full diplomatic relations and the 5th anniversary of China's resumption of its exercise of sovereignty over Macao, is an indication of the good political ties between the two countries, said Sampaio.

The two sides will sign new accords on economic cooperation, and discuss issues on the signing in the near future of cooperation accords on science and technology and culture, he added.

Sampaio visited China in 1997 and was present at the ceremony of China's resumption of its exercise of sovereignty over Macao in 1999.