The Europe unit which had led negotiations for a Brexit deal with Brussels has been disbanded by Boris Johnson.

The civil servants who worked in the Cabinet Office under Olly Robbins, Theresa May’s chief Brexit negotiator, are all thought to have been redeployed to other government departments.

The Times also understands that Mr Robbins, who was moved from his job by Mr Johnson, will announce this week that he is leaving the civil service.

He has been on gardening leave since July after handing over to David Frost, a former political adviser to Mr Johnson who is now his Europe adviser.

A Whitehall source said that Mr Frost had a core team of only four political and civil service advisers working directly for him in