Michael Gove has told environmental protesters “we’ve got the message” as campaigners vow the disruption in London will continue for weeks.
The Environment Secretary’s comments came after some activists glued themselves to a train and others chained themselves to Jeremy Corbyn’s garden fence.
A total of 340 people had been arrested by Wednesday evening during ongoing protests in Parliament Square, Waterloo Bridge, Oxford Circus and Marble Arch this week.
Scotland Yard could not confirm whether or not anyone had been charged with any criminal offences.
Campaigners said the cells in the capital were full and “operating on a one-in, one-out capacity”, while some of those being released from custody have rejoined the protests.
The Metropolitan Police said: “Our custody suites are not full and we are continuing to arrest those who are breaking the law.”
The force added that those continuing to demonstrate in areas where a restriction is in place face prosecution.
Parliament Square, Oxford Circus and Waterloo Bridge are all subject to a condition that protesters should only demonstrate at Marble Arch.
Asked about the Extinction Rebellion protests on the BBC’s The One Show, Mr Gove said: “I do worry sometimes about some of the scenes we’ve seen and some of the activity that goes on.
“So I think it’s appropriate for people to make their feelings known but I also think, we’ve got the message, we understand that action needs to be taken.
“And in fact some of the activity that’s been going on on the streets has actually stopped people doing their jobs and also impeded, for example, people getting around London in a way that’s appropriate.”
Two men and two women from the Extinction Rebellion (XR) group used a bike lock to attach themselves to a fence and glued their hands together outside Jeremy Corbyn’s house in north London on Wednesday.
They said they all support Mr Corbyn but want the Labour Party to go further than declaring a “climate emergency”.
As they left, one protester, Tracee Williams, 55, said: “We just really felt we had to bring it to his front door.”
British Transport Police (BTP) arrested two men and a woman on suspicion of obstructing the railway after activists clambered aboard the carriage of a train at Canary Wharf station on Wednesday morning.
A smartly dressed man and woman glued their hands to the roof before being removed and taken away in a police van.
Activists said they plan to continue their roadblocks, which have affected more than half a million people with road closures, traffic gridlock and disruption to transport and businesses since Monday, until at least next Friday.
Spokeswoman Jayne Forbes told the Press Association: “We would obviously look to go on for two weeks and if we can go on longer then even better.
“It depends on the rebels.
“We have got quite a lot of people committed to do it for the whole two weeks.”
Robin Boardman-Pattison, 21, who earlier walked off during an interview with Sky News, said activists were planning to step up action on the rail and London Underground network.
“We will be escalating our disruption throughout the week,” he said.
“The impact to the Tube system will grow.”
XR, who are demanding a meeting with the Government, says direct action is needed to force authorities to act urgently on climate change and wildlife declines and halt a “sixth mass extinction”.
TV presenter and naturalist Chris Packham joined protesters at Oxford Circus, saying: “I believe the world’s leaders are not acting urgently enough to avert a climate catastrophe.
“As long as it is peaceful and democratic then they can count on my support.”
A YouGov poll of 3,561 UK adults suggested public opinion has swung against the protests, while some Londoners hit out at the group’s “seriously flawed” methods.
The survey results show 52% either “somewhat oppose” or “strongly oppose” the action, compared with 36% who “strongly support” or “somewhat support” it.
Music student Anouska Stahlmann, 20, said her ill mother and elderly grandparents had to walk part of their journey because of the risk of getting stuck in a tunnel while on the Tube.
“I have no issue with wanting to better the environment and we’re fairly conscious of it as a family,” she said.
“Their methods, however, are seriously flawed and are not inclusive of people who want to support the cause.
“I find it awful they’re disintegrating into a rent-a-mob mentality really.
“I’d expect better.”