Extinction Rebellion joined with partner group Animal Rebellion in the fourth day of their fortnightlong climate change protests. Harley McDonald-Eckersall, of Animal Rebellion, said: "We are demanding the Queen end the use of Crown land for industries which are contributing to the climate and ecological emergency and the death of animals."

       A police spokesman said: "Officers encouraged people to leave but as the assembly did not disperse, officers began arresting those who refused to comply."

       Some 236 people have been arrested at the protests so far.

       Tory MP Nickie Aiken said the clean-up after 2019 XR protests cost her London council ￡50,000. An XR spokesman denied there were extra costs to taxpayers.