SIR Keir Starmer’s treatment of socialist MPs has left a “sour taste” in the mouth of the party’s left, ex-MP Ian Mearns stressed today.

The former member for Gateshead, who stepped down last month ahead of July’s general election, blasted the tactics of the party’s right-wing leadership as “disgraceful.”

The damning intervention came after many socialist stalwarts were thrown out of Labour or threatened with deselection, including former leader Jeremy Corbyn and ex-shadow home secretary Diane Abbott.

In a virtual address to the Bakers’ Union’s annual conference in Staffordshire, Mr Mearns said: “Internal party machinations have left a really sour taste in the mouth.

“The tactics of the right of the party are to blame.”

The 67-year-old warned that Labour’s election manifesto — set to be published this week — would likely contain an “awful lot of words without saying too much,” but he urged activists to fight for a stronger new deal for workers.

In an emotional speech, met with a standing ovation, the former chair of the union’s parliamentary group said working with members had been an “informative, exhilarating and entertaining” experience.