THREE former Labour ministers face formal disciplinary action for backing a campaign to force Gordon Brown to call a referendum on the European Union reform treaty.

The outspoken Eurosceptics Gisela Stuart, Frank Field and Kate Hoey were each summoned for an angry rebuke by Geoff Hoon, the government chief whip, and were told that their behaviour was “disgraceful”.

The MPs now face suspension from the parliamentary Labour party if they fail to distance themselves from the cross-party group, I Want a Referendum, which plans

to stoke the debate on the constitutional treaty by running mini-referendums in the seats of pro-EU members.

In a sign of the government’s growing nervousness, Hoon took the unusual step of calling the MPs to his Commons office for an “interview without coffee” in a last ditch attempt to silence them.

One MP said: “Geoff was absolutely furious. He never normally raises his voice, but you could hear the noise two rooms away.”

However, this weekend the rebels remained defiant, promising that they would continue to call for Labour to fulfil its “manifesto pledge” to hold a national ballot.

The campaigners hope to persuade members nervous about losing their seats to change their minds and vote with the rebels in the continuing Commons debate.

The Labour MPs being targeted — who include Bill Rammell, the universities minister defending a majority of 97 in Harlow, Esseex — are understood to be furious that parliamentary colleagues are backing a campaign to destabilise them.

Formal disciplinary proceedings against Hoey, Field and Stuart will begin tomorrow at a meeting of the parliamentary Labour party. The three Eurosceptics have been the subject of regular speculation that they might defect to David Cameron’s Tories.

Field recently turned down an invitation to sit on a Conservative policy forum, while Hoey is a well known supporter of Ulster Unionism and foxhunting.

German-born Stuart, a former Europe minister, is also regarded as something of an outsider. She is married to Derek Scott, a former adviser to Tony Blair and outspoken critic of Brown, who now runs the I Want a Referendum campaign.

One Labour MP, who overheard Hoon’s rebuke of Stuart on Thursday, said: “Geoff normally regards himself more like a modern human resources manager, but this was an old-fashioned whips’ dressing down. He told Gisela, ‘For a Labour MP to actually be targeting fellow colleagues in the PLP who are high profile and potentially vulnerable is completely disgraceful. I want this stopped’.

“At the Ministry of Defence, where Geoff used to work, they used to call these meetings ‘interviews without coffee’. If they don’t back down he may have no option but to withdraw the whip.”

However, a defiant Stuart said that she had no intention of quitting the Eurosceptic campaign’s “advisory group”. She added:

“I am a Labour MP and I want to continue to have a Labour government.”

Hoey and Field went to see Hoon together. “I am absolutely committed to Labour’s election manifesto, which guaranteed a referendum,” said Hoey, a former sports minister. “I am happy to be involved in an all-party campaign to remind all parties of this manifesto commitment.”

Field, a former social services minister, was typically waspish: “The chief whip suggested we should instead campaign in Liberal seats. I am happy to take that idea on board. I am in the business of ensuring that Labour fulfils its manifesto pledge.”

A spokesman for Hoon refused to say what had been discussed.

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