Canadian authorities struggled to tackle a truckers' protest against Covid restrictions which has paralysed the national capital for days and threatens to snowball into a full-blown political crisis for Prime Minister Justin Trudeau.

Ottawa Mayor Jim Watson urged the federal government to appoint a mediator to work with protesters and find a way to defuse the 10-day-long demonstration which has infuriated local residents with incessant honking and diesel fumes.

It comes as a court has granted an interim injunction against the protesters which seeks to stop them from honking horns downtown.

A lawyer brought an application for it as part of a class action launched on behalf of residents.

The injunction request alleges that blasting air horns and train horns "incessantly" was a key tactic of the protesters, "organised and planned by the Defendants to cause serious discomfort and inconvenience" to residents.

Yesterday, Mr Watson declared a state of emergency in the capital, calling the protests an "occupation" and declaring them "out of control."

The "Freedom Convoy" demonstrations began 9 January in western Canada as protests by truckers angry with vaccine requirements when crossing the US-Canadian border, but have morphed into broader protests against Covid-19 health restrictions and Mr Trudeau's government.

Ottawa police have banned people bringing fuel to the rallies

Protest organiser Tamara Lich said activists were willing to engage with the government to find a way out of the crisis, but insisted that pandemic restrictions be eased.

"What we're trying to do right now is reaching out to all of the federal parties so that we can arrange a sit down," Ms Lich said during a meeting streamed on YouTube.

"So that we can start these talks and see how we can move forward, have their mandates and the restrictions lifted, restore Canadians rights and freedoms and go home."

Facing criticism for allowing the centre of the capital to be blocked and many businesses to have to close, yesterday Ottawa police announced new measures to tame the protests by banning people from bringing fuel and other supplies to the rallies.

"Anyone attempting to bring material supports (gas, etc) to the demonstrators could be subject to arrest," the police said on Twitter.

Officers have since arrested several people, seized multiple vehicles and issued hundreds of traffic tickets.

Reacted too strongly

Mr Trudeau, who has been in quarantine after testing positive for Covid-19 a week ago, did not comment on the weekend protests.

On Thursday he ruled out the possibility of deploying the army to disperse the protesters "for now," saying that one must be "very, very cautious before deploying the military in situations against Canadians."

"Trudeau has nothing to gain by going to speak to the demonstrators," Genevieve Tellier, a political scientist at the University of Ottawa, told AFP.

But another political analyst, Frederic Boily of the University of Alberta, said the protests could escalate into a full-blown political crisis.

"Justin Trudeau reacted badly initially," Mr Boily said. "He reacted too strongly and too abruptly at the start of the protests when he tried to paint them as a far-right protest."

Mr Boily added that Mr Trudeau "added fuel to the fire" by turning vaccination into a political issue, especially during last summer's election campaign.

A protester in Ottawa at the weekend demands an end to Covid restrictions

But the opposition also finds itself in a bind politically.

The Conservatives, who will soon be voting to elect their new leader, are themselves divided on the issue of the protests.

"They are afraid that part of their supporters will be tempted by the extreme right, but it is a risky bet for them", said political analyst Daniel Beland.

While only about 10% of Canadian adults remain unvaccinated, as many as 32% of the population support the anti-mandate protests, according to a recent survey.

Similar, if smaller, demonstrations hit the cities of Toronto, Quebec City and Winnipeg over the weekend.