Barclays branches will be disrupted by turning them into “pop-up discos” and “children’s play areas”

The shadow chancellor has told Barclays that he is “on their case” as he backed a direct action campaign against the bank for financing fossil fuel projects.

The Momentum group yesterday confirmed plans to disrupt Barclays branches by turning them into “pop-up discos” and “children’s play areas” in climate-change protests next weekend. Staff would be handed boxes of chocolates to apologise for the inconvenience, the group said.

The support from John McDonnell comes as Labour seeks to capitalise on the popularity of the activism fed by the Extinction Rebellion movement and the 16-year-old Swedish schoolgirl Greta Thunberg.

Labour will use a Commons debate to get MPs to vote on whether to heed her call and declare an “environmental and climate emergency”.

Mr Corbyn praised “the