“I will never ever, ever allow our democracy to be disrupted by unfair protests.”
The climate activists targeted the conservation charity on Tuesday, to some people's surprise.
Campaigners also parked a caravan on the London landmark to demand climate change action.
The activists' protest are expected to trigger "significant disruption".
Covid rules mean police can violently shut down protests like they did on Saturday. Now those powers could become permanent.
The Labour leader’s rebuke marks a shift from party’s position under Jeremy Corbyn, who had praised XR.
Extinction Rebellion Slam 'Ridiculous' Reports Home Office Could Reclassify Them As 'Organised Crime Group'
Priti Patel and Boris Johnson have reportedly asked the Home Office to reclassify the environmental group, The Sunday Telegraph reported.
Priti Patel Accuses Extinction Rebellion Of 'Attack On Democracy' As Activists Block Newspaper Printers
Thirteen activists have been arrested as the group target a number of sites, including the presses for Murdoch-owned titles including The Sun and The Times.
Scotland Yard has been accused of sending "vague threats" to the environmental group on the basis of Covid-19 gathering restrictions – from which XR are exempt.
The protest has been organised to draw attention to the impact of Covid-19 on indigenous people in Brazil.