Labour likewise dismissed the proposal, claiming it had been put forward for political reasons but would fail to unite the Conservative Party.
The issue has clearly aggravated tension, barely within a week of the call for unity by Douglas Hurd, the Foreign Secretary, in a series of meetings with representatives of the pro and anti-European factions.
Other EC states decisively rejected the scheme when Mr Major pressed for it in the Maastricht negotiations as an alternative to a single currency.
Ray Whitney, chairman of the 90- strong Positive European group of Tory backbenchers, said it was the right time to re-examine the idea, which would allow businesses to use a currency with a guaranteed value. 'There is a different spirit of realism and pragmatism,' he said.
But rebels are split between viewing the hard ecu as a back-door route to a single currency, considering it pointless in the light of the Maastricht treaty, and believing any willingness to discuss it as a political blunder on the Prime Minister's part.
Nick Brown, a Labour treasury spokesman, said floating the idea at this stage smacked of 'political rhetoric.' He said: 'For John Major to think he has any credibility over a hard currency is almost comic.' A period of reflection and consideration was what was needed most.
Downing Street, meanwhile, insisted that officials had not instigated weekend reports that Mr Major favoured a revival of his pre-Maastricht proposal for the new currency. 'We are not wedded to any option,' a spokesman said.
Michael Spicer, MP for Worcestershire South, said that while the hard ecu might be a good idea as a convenience currency, under the Maastricht treaty a single currency would become the law of Europe.
Teresa Gorman, MP for Billericay, said the debate was 'thoroughly boring' and unnecessary. 'The idea that the businessman needs it and finds it impossible to do business because of currency changes is a calumny which only politicians can dream up.'
According to some commentators, use of the hard ecu would grow gradually. If and when it became popular and if and when European economies converged, a move to a single currency might occur.
Life after the ERM, page 16