The Tory leader has authorised the party chairman Michael Ancram to write to all Conservatives who hinted that they might back the rebels, telling them that their membership will be considered terminated unless they can demonstrate their loyalty to his satisfaction.
Several senior politicians - including the former Defence Secretary Lord Gilmour of Craigmillar, the veteran Tory "wet" who described Mr Hague's position on Europe as "indefensible", and Sir Julian Critchley, who said he planned to vote for the Pro-European Conservatives - are expected to be expelled immediately.
The former MPs and MEPs who wrote to the Times in the run-up to last week's Euro elections saying they would "find it very difficult to know how best to cast our vote" are also vulnerable. They are likely to receive stern letters from Mr Ancram informing them that they seem to have broken the party's constitution.
Those who could be thrown out include former government whip Sir Robert Hicks, Tim Rathbone, the former MP for Lewes, and Sir David Knox, a former Tory vice-chairman. Nick Scott, the former disabilities minister, is likely to escape censure because he then clarified his position by publishing a letter saying he intended to vote for Mr Hague's party. Dr Adrian Rogers, the former candidate for Exeter, has already been expelled for urging voters to back the UK Independence Party.
The purge of senior "wets" will infuriate Kenneth Clarke, the former Chancellor, and Michael Heseltine, the former Deputy Prime Minister, who are privately unhappy with the Tory leadership's line on the single currency and argue that the party should be a "broad church" including people with more pro-European views.
Although they remained loyal to Mr Hague throughout the European election campaign, they are likely to become more outspoken this week. They have indicated that they will support Britain in Europe, the pro-single currency campaign organised by the Labour peer Lord Hollick. However, they are now insisting that they will attend the launch only if Tony Blair or Gordon Brown is present.
Mr Hague is also planning a reshuffle of his Shadow Cabinet, which could come as early as this week. Ann Widdecombe, the shadow health secretary, is likely to be a major beneficiary. She is thought by the Tory leader to be both effective in the Commons and popular in the country and is likely to be promoted to shadow Home Secretary.
Peter Lilley, the Deputy Leader, is almost certain to lose responsibility for overseeing policy review and may be sacked altogether, although he could be kept on in some capacity, possibly as shadow Foreign Secretary.
Michael Howard, Sir Norman Fowler, and Gillian Shephard have already announced that they intend to stand down from the front bench. Mr Hague is not planning to sack John Redwood, shadow Trade and Industry secretary, who has been described as a possible victim.
Archie Norman, the Asda boss and former Tory chief executive, is set to be promoted to a junior front bench post, although senior Tories believe he is unlikely to be put straight into the shadow Cabinet. Teresa May, Damien Green, Gary Streeter and Liam Fox are all tipped for promotion.Reuse content