Obama extended the invitation at a formal meeting with Hu in Beijing's Great Hall of the People, and Hu accepted it with pleasure, said the China-U.S. Joint Statement issued after the meeting.

China, U.S. to raise cooperation level in science, innovation

China and the United States highly value the fruitful scientific and technological results achieved in the past three decades, and agreed to start dialogue on aviation and railway cooperation, said a joint statement issued after talks between Chinese President Hu Jintao and visiting U.S. President Barack Obama here on Tuesday.

"The two sides applauded the rich achievements in scientific and technological cooperation and exchanges between the two countries over the past 30 years since the signing of the China-U.S. Agreement on Cooperation in Science and Technology," said the statement.

Both sides agreed to further upgrade the level of exchanges and cooperation in scientific and technological innovation through the China-U.S. Joint Commission on Science and Technology Cooperation.

The two countries "look forward to expanding discussions on space science cooperation and starting a dialogue on human space flight and space exploration, based on the principles of transparency, reciprocity and mutual benefit," said the statement.

The two sides will exchange visits of the NASA Administrator and the appropriate Chinese counterpart in 2010, it said.

The two sides also agreed to strengthen cooperation on civil aviation, and to expand the Memorandum of Agreement for Technical Cooperation in the field of Civil Aviation between the Civil Aviation Administration of China (CAAC) and the Federal Aviation Administration of the United States.

Besides the aviation field, Chinese and U.S. officials also hope the Chinese and U.S. public and private bodies to jointly build high speed railways, said the statement.