Tower Bridge had been closed after Extinction Rebellion protesters blocked traffic on the busy Thames crossing on Friday morning.
Demonstrators from the climate group had unfurled a banner reading “End fossil fuels now” from the side of the bridge.
Two people were abseiling from the bridge using suspension cords and have released red flares.
Boats could not travel under the bridge due to the two protestors suspended from it, and were instead forced to go round the side of the bridge, as reported by MyLondon.
Officers cleared the protesters by 11.40am, escorting them into police vehicles, and the bridge was reopened at midday.
According to City of London Police, four protestors were arrested and are being held in police custody.
A statement from Extinction Rebellion says the action took place “on the eve of the April Rebellion which begins tomorrow at 10am in Hyde Park”.
The group plan to gather at Speaker’s Corner in Hyde Park every morning for a week or more, where there will be “regular trainings in nonviolent civil disobedience and resistance tactics” before marching into London to block parts of the city “for as long as possible”.
This morning’s act of protest comes eight days after the group and the Just Stop Oil coalition caused disruption at oil depots across the UK.
Amy Rugg-Easey who took part in the action today, said: “When I volunteered during the COP26 climate conference in Glasgow last year, I learnt from members of indigenous communities from the Amazon rainforest that companies destroying their home are doing it to extract oil, and some of the indigenous environmental campaigners had been killed while defending their home.
She added: “Some of the banks and companies continuing to fund, insure and endorse these projects are based here in London, where those communities cannot reach them, but I can, so I will do what I can to help.”
Frustrated commuters expressed their annoyance at being delayed by the blocked traffic caused by this morning’s protest.
One Twitter user who works in a hospital branded the group “selfish” for delaying him from getting to work.
The group have said their action will continue until the UK government meet their demands, adding that “there will be a decisive shift in tactics from nonviolent civil disobedience to civil resistance”.
This means that they will “no longer ask the government for change, but continue to put [themselves] in the way of the government causing more harm”.
The actions come amid a cost of living crisis in the UK, with a major hike in energy bills that began on April 1.
It also comes as the UK government revealed its energy strategy, in which the Chancellor Rishi Sunak, has asked the Bank of England to support investments in the North Sea, which the group has said “contradicts” the government’s Net Zero strategy.
London mayor Sadiq Khan said that the protest was “counterproductive”.
Speaking at the launch of Labour’s local election campaign in Barnet, north London, he said: “My concern is some of the actions of XR discourage people from joining the campaign and don’t affect government policy.
“I think all campaigns or protests should be peaceful, lawful and safe and I’m concerned that some of the tactics being used are counterproductive”.
