Scores of protesters pitched tents in central Hong Kong suggesting they were in for the long haul after the government called off talks with students amid a two-week standoff that has shaken communist China's capitalist hub.

This morning, protesters awoke after thousands regrouped last night to push their demand for democracy.

Hong Kong Chief Secretary Carrie Lam said the talks with the students were off because of the strident demands for universal suffrage, which she said was not in accordance with the city's mini-constitution, and because of their "illegal" occupation of parts of the city and calls for people to rally.

The political crisis has seen tens of thousands take to the city streets to push for free elections and seek the resignation of Hong Kong leader Leung Chun-ying.

The protesters are well equipped to sit it out, with supply stations stocked with essentials. They also have makeshift showers and dozens of tents pitched where they can sleep.

Scenes of tear gas wafting between some of the world's most valuable buildings, violent clashes, mass disruptions to business and commuter chaos have underscored the challenges Beijing faces in imposing its will on Hong Kong.

Protest numbers have dwindled to just a few hundred people at various sites, but activists have managed to keep up their blockade of some major roads, frustrating some residents.

China rules the former British colony through a "one country, two systems" formula which allows wide-ranging autonomy and freedoms not enjoyed on the mainland and specifies universal suffrage as an eventual goal.