On day two of his Beijing visit, Bush took his human rights pitch from a church service near Tiananmen Square to a public appearance with Hu, a meeting with Premier Wen Jiabao, and finally to an impromptu exchange with reporters.

"I talked about both political and religious freedom," the US president told reporters, adding that he had raised the issue with Hu of political dissidents who "we believe are improperly imprisoned."

Bush also said he had urged Chinese leaders to discuss Tibet's fate with its exiled spiritual leader, the Dalai Lama, and tried to convince them they should invite Vatican leaders to discuss religious freedom.

US Secretary of State Condoleezza Rice said that Washington was complaining "quite vociferously" to Beijing after Chinese authorities took forceful steps to keep dissidents and activists out of sight during Bush's visit.

She also said that "one has to be concerned" over China's military buildup because "there's a question of intent" but that Washington was confident of keeping the region in balance.

Still, both Hu and Bush took pains to emphasize the importance of US-China relations, pledging after a 90-minute meeting at the Great Hall of the People to work through what Hu described as "inevitable" tensions.

As their talks got under way, Boeing signed a four-billion-dollar deal in Beijing to supply seventy 737 aircraft to China between 2006 and 2008 as part of a broader arrangement to eventually supply 150 of the 737s.

"Win-win cooperation is the mainstream of China-US relations," said Hu, who promised to work to reduce economic tensions on issues such as currency reform and China's massive trade surplus with the United States.

Hu said China was "continuously raising the level of human rights" enjoyed by its people but that progress must reflect "China's national conditions" and that the country would have "democratic politics with Chinese characteristics."

The two leaders said they would next meet in the United States in early 2006 -- a visit that will replace Hu's planned trip in September, which was indefinitely postponed because of Hurricane Katrina.

On the economic front, Hu said Beijing would "unswervingly press ahead" with currency reform and "gradually" cut its trade surplus with the United States, which was expected to run to about 200 billion dollars this year.

US officials, who have expressed frustration that similar pledges on economic reform in July and September have not borne fruit, said much more work remained to be done on all those issues.

The two leaders also agreed to pursue joint efforts to defuse the North Korean nuclear crisis through six-country talks, and to ramp up cooperation to battle the spread of deadly bird flu amid fears of a global pandemic.

The US side reported no breakthroughs on Sunday but pointed to less tangible signs of success, with one senior Bush aide insisting that Hu had been more specific in promising to crack down on rampant counterfeiting of US goods.

Tackling another perennial irritant in Sino-US relations, Taiwan, Hu said that Beijing was "committed to peace and stability in the Taiwan Straits" but warned that "we will by no means tolerate so-called Taiwan independence."

Beijing considers Taiwan a renegade province that will eventually be reunited with the mainland.

Earlier, Bush attended services at the government-approved Gangwashi church and suggested that China had made progress toward religious freedom, saying "it wasn't all that long ago that people were not allowed to worship openly."

"A healthy society is a society that welcomes all faiths and gives people a chance to express themselves through worship," said Bush, who accepted a Chinese Bible and wrote "May God Bless the Christians of China" in the guestbook.

On a light note, Bush, a fitness enthusiast, went mountain bike riding with Chinese athletes who are training for the 2008 Beijing Olympics -- and jokingly reported back later that he would not qualify to represent China at the Games.

Bush, who had earlier visited Japan and South Korea, was to wrap up his trip to the region with a brief stop in Mongolia on Monday.