Huge crowds of campaigners are expected as part of a blockade at Dover Eastern Docks from 11am.

Environment protest group Extinction Rebellion (XR) is due to cut off two of the port's primary exit roads and will do so for four hours.

The group previously warned that this will cause major traffic disruption in and around the harbour.

The XR demonstration is already starting to block roads around the A20 near the port.

Chris Atkins, of XR Dover, said: “The government is saying and doing precious little to prepare us for what we know is coming.

“As climate change develops, millions of ordinary Britons will face the real and growing threat of food shortages, hunger and starvation.

“Extreme storms and floods are already causing major crop failures across the world, with high temperatures also hitting livestock agriculture.

“This growing crisis may seem far away now but, as the UK imports around half the food it consumes, we are extremely vulnerable to these climate impacts.

“The government must tell the truth and act now.

"The longer we kick the can down the road, the greater the risks of price hikes, food shortages, hunger and, ultimately, starvation here in Britain.

“We’re sorry for disrupting journeys, but the British public deserves to know the truth.

"If the government refuses to even talk about this, then someone else must.”

The day also includes a family-friendly celebration of music, and information on how to help stave off the threat of starvation.

Similar protests in France and Belgium are coinciding with this blockade.

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