More than 40 demonstrator sat down in the middle of the A20 in Kent, forming roadblocks on two of the main routes into Europe’s busiest port shortly after 8am on Friday.
Lorry drivers could be heard sounding their horns, while some motorists remonstrated with the activists as two groups cut off access at the Eastern Docks roundabout and near the junction with Union Street for the Western Docks.
The Port of Dover said traffic had resumed flowing in and out of the site at 11.21am – however one lane of the A20 remains blocked after two protesters climbed on top of a tanker.
They are reportedly glued to the vehicle, which is draped in an Insulate Britain banner and signs saying “I want my children to survive”, and “Arrested 4 times because I am in mourning for life on earth”.
Kent Police confirmed 39 people had been arrested on suspicion of causing a public nuisance and obstructing a highway following the demonstration.
Chief Superintendent Simon Thompson said: “The impact this disruption had on the local community and port-bound traffic is not lost on us and I would like to thank those adversely affected by it for their patience whilst we made the area safe again.
“Kent Police is working with the other forces, the CPS and partner agencies to gather evidence and ensure there are consequences for those who break the law.”
The demonstration came after the offshoot of Extinction Rebellion was threatened with imprisonment if activists returned to the M25 motorway where they caused chaos five times in the past fortnight.
A spokesperson for the group, which wants the government to insulate and retrofit homes across the UK to cut climate emissions, said: "We are blocking Dover this morning to highlight that fuel poverty is killing people in Dover and across the UK.
“We need a Churchillian response: we must tell the truth about the urgent horror of the climate emergency.
“Change at the necessary speed and scale requires economic disruption.
“We wish it wasn't true, but it is.
“It's why the 2000 fuel protests got a U-turn in policy and gave (Tony) Blair his biggest challenge as prime minister.”
Confirming the protest activity, the Port of Dover said the port remained open but warned the public to check with ferry operators for updates and allow extra time for their journey.
Doug Bannister, chief executive of the Port of Dover, said the port had “implemented its tried and tested resilience plans in order to deal with the impact of the protest”.
He added: “The port has consistently shown its ability to deal with such challenges and today’s targeted activity shows once again the importance and symbolism of Dover to the nation as a critical trade and tourism artery on which the UK continues to rely.
“We are working with our customers and the police authorities in managing the situation and apologise to our community for any disruption being caused by a situation not of our making.”
Kent Police confirmed 17 arrests had been made following the protest.
A spokesperson for the force said: “Kent Police is currently dealing with protest activity which is causing traffic disruption in Dover.
“At around 8.20am on Friday 24 September officers were called to reports that a group of people were obstructing the road on Jubilee Way, a second group were at Snargate Street at the junction with A20 and a third smaller group were on the A20 at the junction with Aycliffe.
“Officers are in attendance and are engaging with the individuals involved and 17 people have been arrested. The Snargate Street and A20 at the junction with Aycliffe sites are now clear.
“Kent Police is aware of the traffic disruption in the area and is working with partner agencies to minimise delays.”
The Port of Dover is Europe’s busiest ferry port, handling 17 per cent of the UK’s trade in goods.
It was used by an average of 6,200 road haulage vehicles every day last year.
The blockage comes amid disruption to supplies across the UK due to a shortage of lorry drivers.
Additional reporting by Press Association
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