Betty Boothroyd last night hit out at Labour for expelling Alastair Campbell – as she revealed that she too had not voted Labour for the first time.

The respected former Commons Speaker – once a Labour MP – branded the expulsion as the 'daftest and most insensitive' decision that the party leadership had made.

The peer – who is a prominent campaigner for a second referendum – would not say who she did vote for at last week's European elections.

Betty Boothroyd followed Alistair Campbell's lead by refusing to vote for her own party

Her intervention came as Jeremy Corbyn faced a mutiny from Remain-supporting party members over its equivocal position on Brexit.

It was accompanied by an #expelmetoo backlash on social media, with other Labour members who voted for pro-Remain parties last week daring the party to throw them out.

Mr Campbell, Tony Blair's former spin doctor, was ousted from Labour on Tuesday after he admitted backing the Liberal Democrats because, unlike his party, they were strongly in favour of a so-called People's Vote. A number of other senior Labour figures confirmed they had voted for different parties in the European polls – and dared the leadership to expel them too.

Baroness Boothroyd, 89, sits as a crossbench member in the House of Lords and she resigned her membership of the Labour Party when she became Speaker in 1992.

She told the Mail: 'The Labour Party seems incapable of making positive leadership decisions of late. Fence-sitting seems to be in vogue. But the decision to expel Alastair Campbell from membership of the party is the daftest, most insensitive decision of all. For the first time in my long life I didn't vote Labour at the European elections and there are no prizes for guessing where my vote went.'

The Dewsbury-born Baroness Boothroyd sat as Labour MP for West Bromwich West between 1973 and 1992. She was then elected the first woman Commons Speaker, at which point she had to renounce her political allegiance.

Alistair Campbell was expelled from Labour after admitting he voted Lib Dem in the EU elections

She now sits in the Lords as a crossbencher, and has become a prominent campaigner for a second referendum – also a policy of the Liberal Democrats. Yesterday Labour's deputy leader said the party's decision to expel Mr Campbell was 'spiteful'. Tom Watson called for an 'amnesty' for those who did not support the party at the European elections, and said members should be 'listened to, not punished'.

A number of other senior figures confirmed they had voted for different parties in the European polls. Former home secretary Charles Clarke, a party member for 47 years, said he had voted Lib Dem, along with ex-MP Fiona MacTaggart, while former defence secretary Bob Ainsworth said he voted Green.

But Labour would not say last night whether they had also been expelled – prompting accusations of double standards. On Monday the party said Mr Campbell had been expelled for 'supporting a political organisation other than the Labour Party'.

Yesterday they claimed it was not his voting Lib Dem that prompted the expulsion, it was the fact he had 'used media appearances to advertise and encourage support for another party'. Mr Clarke called Mr Campbell's expulsion 'a disgrace that only compounds Labour's current political difficulties'. Mr Watson said: 'It is very clear that many thousands of Labour Party members voted for other parties last week. They were disappointed with the position on Brexit that a small number of people on the NEC [Labour's National Executive Committee] inserted into our manifesto.

'They were sending the NEC a message that our position lacked clarity, and they were right.

'It is spiteful to resort to expulsions when the NEC should be listening to members. The politics of intolerance holds no future for the Labour Party. A broad church party requires pluralism and tolerance to survive. There should be an amnesty for members who voted a different way last week. We should be listening to members rather than punishing them.'

Mr Campbell said members of Mr Corbyn's staff were among those who sent 'many, many messages of support' for his decision. He said he will appeal against the expulsion and warned that Labour faces 'oblivion' unless it clarifies its Brexit position.

He described his rapid expulsion as 'strange' and said 'people will inevitably draw the contrast with the lack of rapidity in dealing with cases involving anti-Semitism'.

Labour said 'support for another political party or candidate is incompatible with party membership'.