Rights groups are calling for Washington to pressure China over its crackdown on dissent as U.S. and Chinese officials wrap up their two-day human rights dialogue Tuesday.

The annual closed-door talks are being held in Washington, led by U.S. Assistant Secretary of State Michael Posner and Chen Xu, a senior official in China's Ministry of Foreign Affairs.

The dialogue, now in its 17th round, has become a fixture in U.S.-China relations. But some observers say the talks have produced few human rights improvements in the communist country.

Sophie Richardson of Human Rights Watch says that Beijing uses the talks to say it is engaging on rights issues, but without pursuing meaningful reforms.

“The dialogues are a very convenient mechanism for the Chinese government to effectively 'check the human rights box' … spending a day or two each year sitting through these talks and therefore refusing to discuss human rights issues on any other occasion.”

Human Rights Watch wants the U.S. to put more public pressure on Beijing, which has become increasingly intolerant of dissent ahead of a sensitive once-in-a-generation leadership transition in the Communist Party later this year.

State Department spokesperson Victoria Nuland on Monday promised that several sensitive topics would be discussed during the dialogue, which she says is an integral part of the U.S. effort to build cooperation with China.

“We are always – whether it's at the presidential level, the secretary level, or at this working group level – raising not only individual cases but also our concerns about rule of law, justice for individuals, equality, Tibet.”

China regularly rejects criticism over such issues as U.S. meddling in its affairs. But Nuland says the ability to discuss rights issues with Beijing is proof of a “maturing” U.S.-China relationship.

One issue likely to come up during the dialogue is blind legal activist Chen Guangcheng, who escaped four years of house arrest earlier this year and took refuge in the U.S. embassy in Beijing.

Chen, who is now in temporary exile in the U.S., released a statement this week expressing renewed concern over the fate of his family still in China. Nuland said U.S. officials will continue to raise his situation with Chinese authorities and seek “appropriate handling and no reprisals” against Chen's family.

The human rights talks come as President Barack Obama's national security advisor, Thomas Donilon, met Tuesday in Beijing with Chinese officials to discuss security issues in the Middle East and Asia.