A committee of MPs has called on the UK government to hand the Scottish Parliament new legal powers to hold a referendum.

The Scottish Affairs Committee said a section 30 order (S30) should be used to ensure the referendum is "legally and morally watertight".

It claimed "overwhelming evidence" showed Holyrood did not have the power to hold a legally binding referendum.

The Scottish government said it had "no objection" to an S30 being used.

But it said it would only be acceptable if there were "no Westminster strings attached".

The Scottish Affairs Committee is currently comprised entirely of MPs from the three major pro-union parties - the Conservatives, Labour and Liberal Democrats.

The committee has been taking evidence for its Inquiry into the Referendum on Separation for Scotland.

Its report warned Scotland risked "indefinite legal and political wrangling and future uncertainty" if it was conducted on a "dubious legal basis" which was challenged in the courts.

We have always said that we have absolutely no objection to an S30 Order in regard to the referendum, so long as no Westminster strings are attached Spokesman for Bruce Crawford

Committee chairman Ian Davidson MP said: "It is clear from our evidence that the Scottish Parliament has no powers to hold either a binding or an advisory referendum on constitutional change.

"We believe the best way to proceed is for the government to propose a detailed and specific Section 30 (S30) notice, giving the Scottish Parliament powers to conduct a referendum on separation.

"This S30 notice should be subject to a scrutiny process by the Scottish Affairs Committee and approval by Scotland's MPs."

The SNP government at Holyrood wants to hold a referendum on Scottish independence in the autumn of 2014.

A spokesman for Bruce Crawford, the Cabinet Secretary for Parliamentary Business, said: "We have always said that we have absolutely no objection to an S30 order in regard to the referendum, so long as no Westminster strings are attached - and an order on that basis could be agreed very shortly.

"The real issue is that the terms and timing of the referendum must be decided in Scotland, by the Scottish Parliament - not dictated by Westminster - and that includes a possible 'more powers' option.

"It is only right that these matters are carefully and properly considered, which is exactly what the Scottish government is doing."

A Scotland Office spokesman said: "This report supports the position that we need a legal, fair and decisive referendum for the people of Scotland.

"We have an open offer to the Scottish government to engage with us on securing an S30 order."