Twelve female protesters have handcuffed themselves to lorries which had been parked to deliberately block the main road leading to an oil refinery.
Demonstrators drove the vehicles to the Coryton Oil Refinery in Essex in an attempt to stop traffic getting to and from the site which they accuse of exacerbating climate change, said a spokesman for the Crude Awakening demonstration.
He said a further 500 people were travelling from London to the refinery to join the protest.
The spokesman said both lanes of the road to the UK’s busiest oil depot near Stanford-le-Hope had been blocked to prevent oil tankers from leaving to deliver fuel.
One of the protesters, Terri Orchard, said: “We don’t have a hope of tackling climate change if we don’t find a way to start moving beyond oil.
“Oil companies are devastating local environments, trampling the rights of local communities, and pushing us over the edge to catastrophic climate change.
“We are here at the source of the problem, at the UK’s busiest oil refinery, to stop the flow of oil to London.
“We’re here to put a spanner in the works of the relentless flow of oil and to say no more. This place, this whole industry, must become a thing of the past.”
Protesters had earlier said they planned to mass at three train stations in central London in preparation to move on to a series of targets related to the oil industry.
The demonstration, which is being supported by a number of action groups including Camp for Climate Action and Plane Stupid, is part of a global week of action against the fossil fuel industry.
