The increasing bitterness of the Conservative conflict over Europe was illustrated by Sir Edward yesterday when he attacked the autocratic nature of the new leader.
The former Conservative prime minister told GMTV's Sunday Programme: "One can't help noticing the most popular or the most familiar phrase used by Mr Hague is, 'I will not tolerate'. You can't take that line as a leader of a party if you want to hold the party together with different views."
In a separate interview with BBC television's Breakfast with Frost, Mr Hague put more flesh on his political qualifications about a single currency - adding to the economic block that has been extensively spelled out since he became leader.
Mr Hague said: "We shouldn't say never; we shouldn't rule something out when we don't known how it's going to work, but we also shouldn't say that we're definitely going into it when we don't know how it's going to work.
"The single currency won't be up and running properly with its notes and coins circulating until 2002. Now I say you need to see how that works in good times and bad for several years."
But he then added: "And you need to see whether it means that other major decisions are transferred to European institutions and out of the control of the people of this country, and you need to know all that before you could know whether you were going to join a single currency."
But when Sir Edward was asked about Michael Portillo's view, that the single currency was incompatible with democracy, he said that was appalling nonsense.
"And how anybody who's had his experience can stand up in public and say that, I really don't understand," he said. "There's nothing undemocratic about it."
As for Mr Hague's repudiation of the Tory grandees who wrote a letter of support for Europe to The Independent during the parliamentary break, Sir Edward said: "When I was leader of our party, I never said, 'Well, of course, Churchill and Macmillan, they're all passe; they don't matter, don't pay any attention to them'.
"It's not really quite the way the leader of the party normally behaves ... and so I think that letter might have been treated with some respect."
Sir Edward said that no businessman would dream of ruling something out for 10 years, as Mr Hague had done with the single currency.
There is a strong view in sections of the party that Mr Hague will be challenged for the leadership before the next election, and there is a feeling that if the leadership rules are changed - as currently proposed - to allow an incumbent leader to be ousted with just 41 MPs, or quarter of the parliamentary party, backing a vote of no confidence, then Mr Hague's position would be in severe jeopardy if either Mr Portillo, or Chris Patten, were returned to the Commons.