The United Nations' human rights body said Wednesday it would take up the issue of voting rights in Hong Kong, where activists are railing against Beijing's move to vet local candidates.

The Human Rights Committee, which monitors respect of an international treaty on civil and political rights, will hold a public session on the thorny issue on October 23, spokeswoman Elizabeth Throssel told AFP.

The news follows an announcement by China late last month that Hong Kong's next leader will be vetted by a pro-Beijing committee, dashing hopes for genuine democracy in the former British colony.

The standing committee of China's National People's Congress, or parliament, said candidates for Hong Kong's leadership election in 2017 would be chosen by a pro-Beijing committee.

Democracy activists have warned this will effectively ensure that only pro-Beijing candidates can stand for the position, and have vowed a new "era of civil disobedience" to fight for greater democratic freedoms in the semi-autonomous financial hub.

The Human Rights Committee's spokeswoman said the UN body was not reacting to recent developments in adding Hong Kong to its agenda, calling it a follow-up to a review of China's rights record conducted last October.

During that review, the UN body urged Beijing and Hong Kong to "take all necessary measures to implement universal and equal suffrage," and gave them a year to report back on how they were implementing that and other recommendations.

On October 23, the committee will hear from China, Hong Kong and a range of organisations before determining whether any progress is being made.

The committee's findings will be made public at the end of the session on October 31.