Nigel Farage said Scottish MPs should immediately give up their right to debate or vote on devolved English issues in Westminster.
The Ukip leader said he will write to the 59 Scottish MPs today to ask them to commit to ending their involvement in England-only policies.
Mr Farage told BBC Radio 4’s Today programme: “I think Cameron and Miliband were so lacklustre in the early part of this referendum campaign that they panicked and they made a series of promises on behalf of the English - one, to devolve more powers, but secondly they made a promise to maintain the Barnett Formula whereby the UK taxpayer spends £1,600 more on every Scot than on every English person.
“So, it’s quite interesting to see Mr Cameron today on the steps of Downing Street relieved that he didn’t manage to lose the union but now panicked by the English question.
“I think that short-term, as far as English voters are concerned, I’m going to write today to all 59 Scottish MPs and I’m going to say to them in the spirit of finding a fair settlement for the United Kingdom, will you please commit from today not to take part in debates or votes in Westminster on English devolved issues.
“Short-term that’s what we can do. Longer-term, and I think all the constitutional experts talking on your show say, this stuff is complicated, getting this right matters as it will be for many, many decades to come and I really do think now we absolutely need to have a constitutional convention to talk about how we create a fair, federal United Kingdom.
“That process is vital. All I’ve heard from Mr Cameron is that William Hague will head up some committee to discuss the English question and I simply don’t think that’s enough.”