Hong Kong pro-democracy lawmakers failed in an unprecedented bid Wednesday to impeach the city's embattled Beijing-backed leader, after they accused him of breaking housing laws and urged him to quit.

The city's first impeachment motion, which accused Leung Chun-ying of lying, dereliction of duty and serious breaches of the law in a row stemming from illegal structures at his luxury home, was denied after eight hours of debate.

The 27 pro-democracy lawmakers who signed the joint motion -- which they said was a symbolic move -- voted in favour, while 37 voted against in the 70-seat legislature which is dominated by pro-Beijing members.

Wednesday's vote followed a protest on New Year's Day in which tens of thousands took to the streets to urge Leung to quit and to press for greater democracy, 15 years after the city returned to Chinese rule.

The former British colony maintains a semi-autonomous status, with its own legal and judicial system, but cannot choose its leader through the popular vote.

Leung took office in July after he was picked by a 1,200-strong election committee dominated by pro-Beijing elites, amid rising anger over what many perceive to be China's meddling in local affairs.

China has said the chief executive could be directly elected in 2017 at the earliest, with the legislature following by 2020.

Unauthorised structures are a politically sensitive issue in the space-starved city of seven million and demonstrators have used the scandal to press for universal suffrage in choosing Hong Kong's leader.

Leung secured the chief executive role after criticising his rival Henry Tang over illegal structures at Tang's home.

But he has since acknowledged and apologised for structures at his own home which were built without planning permission.

Maverick lawmaker "Long Hair" Leung Kwok-hung, wearing a T-shirt reading "We topple a tyrant", accused the new leader of lying about his own structures during campaigning when he presented the impeachment motion earlier Wednesday.

"He has used dishonest ways to win the election," he said.

Chief Secretary Carrie Lam, second in command in Leung's administration, said the motion was unnecessary and urged lawmakers to work together on policy and livelihood issues.

But Democratic Party chairwoman Emily Lau said the motion was a symbolic gesture to show the deepening public mistrust toward Leung, claiming the leader had "cheated his way to power".

"This is the first time we have a motion in the legislature to impeach a cheating chief executive," she said.

If the motion had been passed, the city's highest court would have had to initiate an investigation. At least two-thirds of the legislature would need to endorse a guilty finding before Leung could be removed from office.

Earlier, rival protesters traded barbs outside the legislature and security personnel had to step in at one point when an angry pro-government supporter charged towards the rival group, TV footage showed.

Leung's popularity ratings have fallen since the controversy, with discontent over issues including sky-high property prices and anti-Beijing sentiment remaining high.