Hilary Benn, the shadow foreign secretary, and Andy Burnham, the shadow home secretary, have taken the highly unusual step of offering to swap jobs in an attempt to hang on to senior positions before Jeremy Corbyn’s first reshuffle.

The Labour leader will start formal discussions with colleagues today over a small number of changes to his senior team, dubbed the “revenge reshuffle”. The moves are designed to sideline critics, boost the number of women in senior jobs and shift shadow cabinet members who fundamentally disagree with the leader over their portfolios.

Michael Dugher, the shadow culture secretary, who is also vulnerable, went on the offensive yesterday, warning that Mr Corbyn would be left with a “politburo of seven” if he moved against his senior critics.