Hong Kong's leader admitted on Saturday that the frustration among young people over a lack of "upward mobility" was fueling mass protests calling for free elections in the city.

Chief executive Leung Chun-ying was speaking at a government committee meeting on poverty, weeks after he shocked ordinary Hong Kongers by saying open elections were not feasible because they would result in the poor dominating politics.

Hong Kong police used pepper spray and arrested 80 people Tuesday as they moved to clear a city street blocked by pro-democracy demonstrators for nearly two months.

Officers in helmets, with some carrying batons, faced off against dozens of protesters at the site in Mongkok district, the scene of some of the most violent clashes since the sit-ins began at three separate intersections in the city on September 28.

A small group of protesters gathered outside Hong Kong's British consulate on Friday to accuse the former colonial power of failing to stop China from wielding undue influence over elections and threatening freedoms guaranteed in a joint treaty.

About 30 people assembled outside the building in the city's Admiralty district, some waving the yellow umbrellas that are the symbol of pro-democracy occupations that have blocked roads in key districts for nearly two months.

Hong Kong authorities on Tuesday cleared part of the city's main pro-democracy protest camp, the first of several planned evictions to shrink mass sit-ins that have blocked major thoroughfares for seven weeks.

There was no resistance from demonstrators as workers dismantled metal barricades blocking access to a skyscraper opposite government headquarters, on the edge of the sprawling camp in the central Admiralty district. 

Hong Kong bailiffs and police are planning to take action at pro-democracy protest sites in the city, as pressure grows on demonstrators to leave, the government said Tuesday.

Deputy leader Carrie Lam warned there was currently "no room for negotiations" between the authorities and protesters, urging them to move out of rally sites after a court authorized bailiffs to call on police if they were stopped from carrying out clearances.

Hong Kong protest leaders made a formal request Friday to speak with China over political reform, calling on a pro-Beijing politician to act as their mediator.

Protest numbers have dwindled since mass rallies mobilised tens of thousands demanding fully free elections for the city's next leader. 

A prominent businesswoman has sparked outrage in Hong Kong by comparing the city's pro-democracy protesters to African-American slaves, suggesting they might need to "wait for a while" to win the freedoms they are seeking.

"American slaves were liberated in 1861 but did not get voting rights until 107 years later, so why can't Hong Kong wait for a while?" Laura Cha, an HSBC board member, was quoted as saying by The Standard newspaper on Friday.

Hong Kong's democracy protesters are considering travelling to Beijing to directly petition Communist authorities as the Chinese capital hosts U.S. President Barack Obama and other world leaders at an upcoming summit.

The protesters have held continuous street rallies for a month, demanding free leadership elections for the semi-autonomous city in 2017.

A senior Hong Kong lawmaker was expelled from a prestigious Chinese government body Wednesday, in a sign that Beijing will not tolerate dissent from loyalists over pro-democracy protests in the semi-autonomous city.

James Tien had his "qualifications revoked" as a member of the Chinese People's Political Consultative Conference (CPPCC), the state-run China News Service said.

Two Hong Kong expats set off Wednesday on an ultramarathon course in the shape of a giant umbrella to support ongoing pro-democracy protests in the southern Chinese city.