The operation on Friday afternoon came after a request from the National Capital Authority to remove structures on Commonwealth land without a permit.

Protesters had been camped out on the site since December, and have been linked to the "sovereign citizen" movement.

The group has also been linked to a fire that damaged part of Old Parliament House late last month.

Police ordered the protesters to remove all tents, caravans, vehicles and camping equipment by 4pm, telling the demonstrators through a loudspeaker.

They said camping within the parliamentary triangle without a permit constituted a breach of Commonwealth law.

At 4.15pm police moved in and began asking individuals to remove their equipment and vehicles.

Some people were seen to voluntarily pack their cars.

But officers then started physically dismantling tents and bundling them in a collection van.

No arrests were made during the operation.

Police also took away personal items from the site such as barbecues, while removing other temporary structures with angle grinders.

An ACT police spokesman said campers on the site had been told of other camping areas in Canberra to set up.

"Today's actions don't prohibit any person peacefully protesting if they wish," the spokesman said.

"However, without the approval of the NCA, no persons will be allowed to camp or park on the grounds in front and surrounding Old Parliament House."

Some protesters were shouting messages such as "you will regret it" as officers moved in.

There were tense scenes between police and protesters, but the incident did not turn violent.

Following the dismantling of tents, protesters moved to surround the nearby Aboriginal Tent Embassy and called embassy members "sellouts".

People at the tent embassy were also seen yelling back at the group of protesters.

The camp clearance followed a court hearing for two men charged over a December 30 protest which saw the doors of Old Parliament House set on fire.

Protesters from the "Muckudda Camp" on Thursday sought to enter Parliament House but were prevented by police, with a number of people arrested in the forecourt.

The protesters have also called for people to storm Old Parliament House on Saturday.

The group has been arguing against COVID-19 vaccinations and calling for the federal government to be "evicted", among other issues.

Their Facebook page includes promotion of unproven COVID-19 treatments.

Representatives of the nearby Aboriginal Tent Embassy, which celebrates its 50th anniversary this year, have distanced themselves from the protesters.

In an Instagram post, an embassy representative said the protesters were "breeding this cult-like mentality", fearing there was "potential for people to get seriously hurt".

Local Ngunnawal elders have also asked the protesters to leave.

The ACT Greens said it was an opportunity to stand in solidarity with the Tent Embassy and against "conspiracy theorists and the far right".

"Rather than bring even more attention to this new group of protesters, we want to use the coming days to celebrate the Aboriginal Tent Embassy, share their history and reflect on what 50 years of struggle can teach us," they said.

The Tent Embassy began on January 26, 1972, with four men sitting under a beach umbrella protesting the McMahon government's approach to Aboriginal land rights.

Australian Associated Press