The attempt by the Tory leader to force the two former cabinet ministers into line came after two former Conservative MEPs announcedplans to run a list of pro-euro candidates against official Tory candidates in June.
The threat to expel two of the major players remaining on the Tory benches exposed tensions that are threatening to tear the party apart.
But Mr Hague's warning could not have been more explicit. "Let me make this very clear. I expect all Conservative MPs without exception to campaign for official candidates in the coming European elections and any who do not will be out on their ear. Let's be clear about that."
His threat was an attempt to stop speculation about a breakaway party or a fresh challenge to his leadership after weekend disclosures that Mr Heseltine had been briefed by the Chancellor before Tony Blair's statement last Tuesday signalling Britain's determination to prepare for entry to the euro after a referendum.
Mr Heseltine had planned to lie low until after the European elections, but the strength of the Prime Minister's support for the euro forced him into the open, talking for the first time about an "alignment" with the Government in support of Britain's entry. One Euro-sceptic Tory MP said: "They are not likely to be mad enough to openly campaign for candidates who are not official Tory candidates, but this is to show they have to toe the line."
Mr Blair today reinforces his belief that the euro would bring stability to Europe in an interview for La Repubblica newspaper before flying to Italy tomorrow to address a meeting of European socialist parties where he will call for "new radicalism" in Europe.
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