Dame Emma Thompson has rallied cheering Extinction Rebellion (XR) activists blocking London’s busiest shopping street and declared “our planet is in serious trouble”.

The Oscar-winning British actress climbed onto a pink boat at Oxford Circus and addressed crowds on Good Friday as the campaign group declared a separate protest at Heathrow Airport was over.

“We are here in this little island of sanity and it makes me so happy to be able to join you all and to add my voice to the young people here who have inspired a whole new movement,” she said to cheers of support.

Several hours later, shortly before 5.30pm, after protesters were removed from the boat, the Metropolitan Police said arrest numbers for the day had reached 106, bringing the total since Monday to 682.

“The serious disruption the demonstrations are causing to people in London and beyond is unacceptable and we completely understand the concern it is causing to those who are disrupted by it,” a tweet said.

Speaking to reporters at Oxford Circus, Dame Emma said her generation had failed to protect the planet for young people.

The actress, who also joined demonstrators on Thursday, added: “We have seriously failed them and our planet is in serious trouble, we have much, much less time than we thought.

“I have seen the evidence for myself and I really care about my children and grandchildren enough to want to be here today to stand with the next generation.”

The Love Actually actress also challenged critics who have said demonstrators are using the protests to have fun.

“If you can’t have fun whilst saving the planet, what’s the point?” she asked.

“Protest should always have a sense of joy in it because what we are protesting about is saving this extraordinary home of ours and also celebrating the passion and inspiring energy of this young generation.”

Extinction Rebellion protests
The actress also posed for selfies with Extinction Rebellion demonstrators (Jonathan Brady/PA)

Shortly after Dame Emma’s address, dozens of police officers encircled the boat and told bystanders there was an ordinance to clear the area.

Officers closed off the whole junction of Oxford Street and Regent Street, letting people out but not in.

Dame Emma left the protest before specialist officers arrived to remove people from the frame of the boat.

A handful of activists were carried or led away by officers, while people who tried to break into the cordon were pushed back.

Earlier, on Friday morning, about 20 activists, most of them under 17, had staged a brief demonstration on roads near Heathrow Airport.

Standing close to a tunnel which leads to terminals two and three, they unfurled a black banner with the message: “Are we the last generation?”

Several police officers watched over the group before an XR spokesman announced before midday there were no further plans to cause disruption at the airport.

All roads remained open during the demonstration, which is part of a two-week campaign that began in central London on Monday.

Extinction Rebellion demonstrators at Heathrow Airport
Extinction Rebellion demonstrators at Heathrow Airport (Aaron Chown/PA)

Heathrow previously said it was “working with authorities” to remain business as usual.

Waterloo Bridge has now been blocked by demonstrators for five days.

Ten people had been charged by the Met by Thursday night and three others arrested by British Transport Police were remanded in custody after they appeared in court accused of obstructing trains at Canary Wharf.

Routes are also blocked around Parliament Square and Marble Arch, and Home Secretary Sajid Javid has urged police to use the “full force of the law”.

“I totally condemn any protesters who are stepping outside the boundaries of the law,” Mr Javid said.

“They have no right to cause misery for the millions of people who are trying to lead their daily lives.”

Ken Marsh, chairman of the Metropolitan Police Federation, told BBC Breakfast the protests were “very, very difficult” to handle and could cost “millions”.

Extinction Rebellion protests
Police take control of Extinction Rebellion’s ‘Tell the Truth’ boat, as protests continue at Oxford Circus in London.

He said: “The sufferers will be the communities in the local boroughs where officers are being taken from the community areas and the funding and money has to be found to deal with what we are doing.”

XR has pledged to continue causing disruption until its demands are met.

They want the Government to declare a climate emergency and take action to reduce greenhouse gas emissions to net zero by 2025.