The UK Government has been warned it faces an English ''backlash'' unless it cuts the powers of Scottish MPs.
The role of Scottish MPs is being questioned
The Conservatives used a Westminster debate to call for Scottish MPs not to take part in the upcoming Commons vote on university tuition fees.
It raised the West Lothian Question, the relative voting rights of MPs in Scotland and other parts of the UK.
The Tories insist it is wrong for Scottish MPs to back higher fees for England, but not for Scotland.
The prime minister faces a key vote on university funding next week.
Education is a devolved matter and MSPs have rejected plans for top-up fees north of the border.
The Conservatives argue that, as a matter of principle, Scottish MPs should not be able to vote on matters in England such as education when Holyrood has responsibility for that and other devolved policy areas north of the border.
Shadow Scottish Secretary Peter Duncan, the only Tory MP in Scotland, urged all Scottish MPs to abstain on next Tuesday's vote on university
Mr Duncan said: "It does nothing for the cause of stable devolution and good government across the UK, for MPs representing Scottish constituencies like my own, to be continuing to seek to vote in legislation in this House, where the equivalent power has been devolved to the Scottish Parliament."
This "travesty" was compounded because the Scottish Labour Party had
"explicitly ruled out" the policy for Scotland, he protested.
Mr Duncan told a packed and noisy Commons: "Is it any wonder that resentment is now building over Tony's tartan army?"
Anne McGuire: "Equal rights"
Downing Street and ministers believe all MPs should be able to vote on all matters discussed at Westminster.
They say changing the present system could lead to two classes of MPs.
Junior Scotland Office minister Anne McGuire accused the
Tories of launching a "tawdry exercise" for short-term political gain.
"All members of this House should have equal rights and equal responsibilities," she said.
The opposition's motion calling for Scottish MPs to abstain on issues devolved to the Scottish Parliament was defeated by 377 votes to 142, a government majority of 235.
Meanwhile, former Scottish education minister, Sam Galbraith, has claimed that student tuition fees have not been scrapped north of the border.
He told the BBC's Newsnight Scotland programme that the move amounted to a confidence trick.
Mr Galbraith said: "This is a con that the Liberals convinced themselves of, they (fees) were switched from the front to the back.
"And that's what is happening in England as well, they're taking the upfront payments, which we used to have, and switching them to post-graduation and I think that's a good principle."
The former minister believes he can pave the way for a U-turn on the issue of fees in Scotland.
But Deputy First Minister Jim Wallace has dismissed his claims.
"Sam's got it wrong, there are no tuition fees in Scotland, paid by Scottish students attending Scottish higher education institutions.
"The fees are funded by the Scottish Executive, there is a graduate endowment which is only paid by those who graduate, and even then there is a considerable range of graduates who are exempt."