President Bush is in Seoul en route to the Olympic opening ceremony
President Bush has urged China to allow more freedom of expression and worship.
Speaking in South Korea before he goes on to Beijing for the Olympics on Friday, Mr Bush said its pre-Olympics crackdown on dissent was "a mistake".
He also held a press conference with South Korean President Lee Myung-Bak, in which they spoke about strengthening their military alliance.
They also welcomed progress in efforts to disarm North Korea, but emphasised that much more needed to be done.
"They've got to... show us a verification regime that we can trust," Mr Bush said.
The two leaders also pledged to work hard to get their respective legislatures to ratify a free trade agreement.
Before the summit meeting, President Bush brushed off the protests that have greeted his trip to Seoul.
"I enjoy coming to a free society where people are able to express their opinions," he said, referring to the few thousand demonstrators opposing his visit because of the recent deal to restart imports of US beef, which protesters believe may carry the risk of mad cow disease.
But there was also a larger counter-demonstration, that saw people waving US flags and carrying welcome banners.
Anti and pro-US protesters stage rallies in Seoul
Freedom of expression
"I have been meeting Chinese leaders for seven and a half years, and my message has been the same: you should not fear religious people in your society," Mr Bush told reporters.
"As a matter of fact, religious people will make your society a better place. You ought to welcome people being able to express their minds."
Critics say Mr Bush should have boycotted the opening ceremony of the Olympic Games because of China's human rights record, but the US leader defended his decision.
"This is an athletics event. But it's also an opportunity to say to the Chinese people, we respect your traditions, we respect your history," he said.
"The reason I'm going to the Olympics is twofold - one, to show my respect for the people of China, and two, to cheer on the US team."
From South Korea Mr Bush goes to the Thai capital, Bangkok, where he is expected to address the issue of Burma.
Then he is due to fly to Beijing in time for the opening ceremony of the Olympic Games on 8 August.
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