Mr Hague yesterday offered his party the firm smack of leadership, with a warning that the party would oppose next week's second reading of the Amsterdam Treaty, and that any frontbenchers who could not swallow his Euro-sceptic line should resign now, rather than generate continuing tension.
On a brief campaign visit to the Paisley by-election campaign, Mr Hague said: "It's always disappointing when somebody resigns, but it is better they resign if they have a genuine disagreement with the leader of the party than if we try to cover it up indefinitely and always have the tension that brings."
As for next Tuesday's Commons vote on the Amsterdam Treaty - the next big bone of contention with his own pro-European dissidents - Mr Hague said: "I don't think we should have too much difficulty on that, if everybody remembers what they campaigned on in the general election."
But in a warning of continuing conflict ahead, Kenneth Clarke suggested that if the Shadow Cabinet wanted to perform a head-stand on the single currency, it must not expect him to follow suit.
Mr Clarke, the former Chancellor of the Exchequer, told a British travel agents' convention in Tenerife: "Now we have a government that is saying `Let's wait a little longer', and an Opposition that is saying `Let's wait - and wait'."
However, in a stark condemnation of the new stance taken by Mr Hague and his colleagues, he added: "If the Shadow Cabinet suddenly wants to change the policy of the Conservative Party for the last 30 years, it can't conceivably imagine that people who've been in office for years and years, taking a different view, were going to agree."
The political pit-falls threatened by the single currency spread to the Government yesterday, when ministers were again warned that Britain would have to re-join the Exchange Rate Mechanism before entering the euro currency.
Probationary membership of the ERM has already been ruled out by both the Prime Minister, Tony Blair, and Gordon Brown, the Chancellor of the Exchequer, although the Governor of the Bank of England suggested yesterday that Britain might have to shadow the tax policies of "euroland" before going into the single currency.
The Prime Minister's office said it was no longer a matter of "cast-iron necessity" to join the Exchange Rate Mechanism before joining the single currency, as laid by the Maastricht Treaty.
Hans Teitmeyer, President of the German Bundesbank, said in Aachen, Germany, said that if countries did not join the first wave of the currency in 1999, they would have to belong to the ERM for two years to become eligible for subsequent single currency membership.
"If they want to join later, the UK must have participated in the Exchange Rate Mechanism for two years," Mr Teitmeyer said.
More ominously for the Government, Patrick Child, spokesman for the European Union Commissioner for monetary union, Yves-Thibault de Silguy, said: "The Commission's view and the view of the majority of other member states is that one of the conditions for participation in EMU is prior membership of the Exchange Rate Mechanism.
"One of the criteria [in the Treaty] requires observance of the normal fluctuation margins of the ERM of the European Monetary System without severe tension. The treaty text is clear."
David Heathcoat-Amory, a Conservative Treasury spokesman, said that Mr Brown had been given a humiliating slap-down.
"Mr Brown must explain what action he will take if he fails to win a waiver of the Maastricht Treaty's requirement," he said. "Otherwise, there will be a growing suspicion that his week-old Economic and Monetary Union Policy is already falling apart at the seams."