BEIJING: US Secretary of State John Kerry said Saturday he urged Chinese leaders to support Internet freedom and promised to look into whether American companies help Beijing curb access to online material.

"Obviously, we think that Chinese economy will be stronger with greater freedom of the internet," Kerry said at a meeting with bloggers following talks with Chinese leaders.

Kerry met earlier with President Xi Jinping and other senior officials to underscore the Obama administration's commitment to refocusing US foreign policy on the Asia-Pacific. He urged Beijing to convince neighboring North Korea to return to stalled nuclear disarmament talks.

During the 40-minute meeting Saturday, the bloggers appealed to Kerry to support Chinese human rights activists and freer use of the Internet.

Communist leaders encourage Internet use for education and business but use an extensive system of monitoring and filters to try to block access to material deemed subversive or obscene.

Zhang Jialong, who reports on finance for Tencent Finance, part of China's largest social media company, asked whether the United States would get together with the "Chinese who aspire for freedom" and help "tear down the great Internet firewall." He complained US companies were helping Beijing block access to Internet use and social media services such as Twitter.

Kerry said it was the first time he had heard complaints US companies were helping the Chinese government control Internet access and that he would check into that.

Zhang, whose microblog has 110,000 followers, was detained for three days in 2011 after posting comments about dissident artist Ai Weiwei's troubles with Chinese authorities.

Zhang said the situation for political and human rights activists has not improved.

He mentioned Xu Zhiyong, who founded the New Citizens movement to promote clean governance and fairness in education and was sentenced in January to four years in prison, and Liu Xiaobo, who is serving an 11-year prison sentence after he disseminated the Charter '08 document calling for democracy. His wife, Liu Xia, has been confined to their home since 2011 but was rushed to a hospital this week with a heart condition.

Kerry did not respond directly when asked whether he would visit Liu Xia, but said he raised the issue of human rights at high levels.

"We constantly press these issues at all of our meetings, whether it is in the United States or here, at every level, and we will continue to do so," Kerry said.