Stanley Johnson gives backing to activists as Met reduce the number of activists’ sites from 12 to six

The prime minister’s father has told a crowd at Extinction Rebellion’s London demonstrations he backs their methods and is proud to call himself an “uncooperative crusty”.

Stanley Johnson was responding to a question about comments made by his son, who called environmental protesters occupying sites across Westminster “uncooperative crusties” in “heaving hemp bivouacs”.

Speaking on a panel from a stage set up by protesters in Trafalgar Square, Johnson said: “On the point of non-cooperative crusties, I wear that badge with pride.

“It’s one of the nicest things that has been said about me for a long time. A non-cooperative crusty, absolutely superb – do they taste good? That’s my thought, I think they do.”

On Wednesday, police said they had arrested 800 people in the past two days – approaching the number of arrests made during the Extinction Rebellion protests in April – and seized equipment including tents, toilets and generators.

Q&A What are Extinction Rebellion's key demands? Show Hide The UK group of Extinction Rebellion has three core demands: 1) Tell the truth

The government must tell the truth about the scale of the ecological crisis by declaring a climate emergency, “working with other groups and institutions to communicate the urgent need for change”. 2) Net zero emissions by 2025

The UK must drastically cut its greenhouse gas emissions, hitting net zero by 2025. 3) Citizens’ assembly

The government must create a citizens’ assembly to hear evidence and devise policy to tackle the climate crisis. Citizens’ assemblies bring together ordinary people to investigate, discuss and make recommendations on how to respond, in this case, to the ecological emergency. In the US activists have added a further demand: “A just transition that prioritises the most vulnerable and indigenous sovereignty [and] establishes reparations and remediation led by and for black people, indigenous people, people of colour and poor communities for years of environmental injustice.” Matthew Taylor

A senior officer said it was “significant” for the Metropolitan police that they had managed to reduce the number of Extinction Rebellion sites from 12 to six by Tuesday night.

The deputy assistant commissioner Laurence Taylor said the operation was complex and it took a minimum of four officers to carry away any activist who refused to stand when arrested. It could take an hour to remove someone who had glued themselves to street furniture and hours to remove those who had used bicycle D-locks.

He said the Met had also made provisions for holding cells for more than 1,000 people.

Police were preparing to prioritise the clearing of key sites to facilitate events next week, including the state opening of parliament.

Extinction Rebellion activists have revealed plans to shut down London City airport for three days from Thursday morning in what they said would include a “Hong Kong-style” occupation of the terminal building.

Protesters will set off from various sites they have been occupying since Monday to highlight what they describe as the incompatibility of the planned £2bn expansion of the airport with the climate and ecological emergency declared by parliament.

Rupert Read, an Extinction Rebellion spokesman, said: “It is used disproportionately by private jets and by financiers, businesspeople and other members of the polluter elite flying in and out of the City of London, when often they could do what they need just as well by using digital telecommunications. This has to stop, and Extinction Rebellion are here to stop it.”

Later on Wednesday, activists criticised the manner in which tents were removed from Trafalgar Square, where police had been directing demonstrators to continue their protest.

“They just came and took the kitchen and all of the tents. We were just sitting down and they were just trampling on people,” one witness said.

Police also moved on protesters at Horse Guards Parade at about 3.30pm, removing gazebos and kitchens set up in the road.

Facebook Twitter Pinterest Extinction Rebellion protestors and a police officer near Downing Street. Photograph: Frank Augstein/AP

Johnson had appeared at Trafalgar Square earlier in the day on a panel of political figures, including Siobhan Benita, the Liberal Democrat candidate for London mayor, Skeena Rathor, a Labour councillor from Stroud, and Read, a Green party activist, addressing the question: “Can traditional politics rise to the challenge of the climate and ecological emergency?”

Most of those speaking suggested the political system required major modifications to answer environmental problems. But Johnson suggested meaningful change could be achieved only through traditional party politics – with a little prodding from non-violent protest movements such as Extinction Rebellion.

“Can you use the present system? Is it good? Well, I tell you it is good, because it’s the only one we’ve got and we have to use this system,” he said.

“But this is the point: what really influences politicians is the sense that out there in the streets, out there in the post offices, out there in the great wide world, there is a great mass of people who approve of what they want.

“I would say you have exactly the right things in mind here. I would say, for example, your target of bringing the net-zero carbon emission date down from 2050 to 2025 – fine, go for it; it is doable.”

Johnson suggested environmental protesters had Margaret Thatcher to thank for beginning moves to tackle pollution. He pointed out that historically, the UK had the second-highest cumulative emissions of any country, behind the US.

“So we do have a responsibility here, we can deliver on that responsibility, and I do congratulate you all for coming. Don’t get stuck with glue somewhere you don’t want to get stuck. I don’t promise to do anything illegal … I mean, I can’t. Your force comes from the fact that you are wedded to peaceful protest and you are not going to break the law,” he said.

Play Video Women breastfeed and bottle-feed babies at Extinction Rebellion 'nurse-in' – video

As Johnson spoke, there were arrests nearby as police blocked a procession of nursing mothers from marching on Downing Street. Parents and their children had earlier gathered by the Queen Elizabeth II centre before marching. They staged a sit-down protest and “mass nurse-in” on Whitehall after being prevented from reaching their intended destination.

Lorna Greenwood, from Lewisham, south-east London, who helped organise the protest, said: “We are bringing our babies to the heart of government to say these are the lives that are going to be most at risk from the climate crisis.

“Babies have already died all over the world, are dying and continue to die, and we’re begging for their lives and futures.”