Image copyright other Image caption There are currently 59 Scottish seats in the House of Commons

The proposed date of Scottish independence should be delayed if it is not in the best interests of the rest of the UK, a House of Lords report has said.

The recommendation was made by peers on the constitution committee.

They also said MPs for Scottish seats should not be allowed to negotiate for the rest of the UK on the terms of independence.

The SNP said the House of Lords was an "undemocratic anachronism".

The Scottish government has proposed 24 March 2016 as a realistic date for Scotland's independence day, which would allow about 18 months for negotiations to be concluded if there is a "Yes" vote in the referendum on 18 September.

The prime minister should feel under no obligation to conclude negotiations by March 2016 Baroness Jay of Paddington

Under that timetable, elections scheduled for 5 May 2016 would be the first to an independent Scottish parliament.

But Labour peer Baroness Jay of Paddington, who chairs the constitution committee, urged the UK government to "put the rest of the UK's interest first" in the event of independence negotiations.

She said: "The prime minister should feel under no obligation to conclude negotiations by March 2016.

"The Scottish government's proposed timetable has no legal or constitutional standing."

Peers on the committee said MPs for Scottish constituencies should retain their seats until the day of independence.

But it said their first duty would be to their constituents in Scotland rather than the rest of the UK.

To be lectured by them about timetables and for democratic processes is something that could only happen in Westminster Angus MacNeil, SNP MP

This would prevent MPs who represent Scottish seats negotiating for the rest of the UK on the terms of independence, scrutinising the UK's negotiating team or ratifying a resulting agreement, the committee argued.

Those affected would include politicians such as Danny Alexander, the Chief Secretary to the Treasury, as well as Secretary of State for Scotland Alistair Carmichael, former Chancellor Alistair Darling and former Prime Minister Gordon Brown.

Senior Tories urged Prime Minister David Cameron in March to block Scots from voting in the 2015 general election.

The peers' conclusion is in line with the Scottish government's White Paper on independence, which argues people must be represented politically at UK level until the day of independence.

The Scottish government is in the process of setting up what First Minister Alex Salmond has described as a non-partisan Team Scotland to negotiate on behalf of Scotland if there is a "Yes" vote.

This would include politicians from across the political spectrum, as well as key experts from outside politics.

'Continuator state'

The committee also said that the wider status of MPs for Scottish constituencies, in terms of their ability to take part in other Commons proceedings not relevant to Scotland, would have to be decided before the 2015 general election if there were a "Yes" vote in the referendum on 18 September.

The committee concluded that in the event of Scottish independence the remainder of the UK would be the "continuator" state and so retain its current international status and treaty obligations, as well as UK institutions such as the BBC and the Bank of England.

Scotland would become a new "successor" state and would not have any automatic claim on those institutions, it claimed.

Other conclusions reached by the committee included:

There is a potential risk of Scotland entering a period of "constitutional limbo" following a "Yes" vote whereby the UK government ceased to represent Scotland's interests but arrangements were not yet in place for the Scottish government to represent Scotland internationally.

If there is a "Yes" vote the negotiating team for the rest of the UK should be a small team from the UK government, rather than cross-party. That team should consult the official opposition and the Welsh and Northern Irish Executives.

An Act of Parliament would be required to give the Scottish government power to negotiate with the UK government following a "Yes" vote; it should also set up the negotiating team for the rest of the UK.

If, in the event of independence, Scotland were to establish its own Supreme Court, justices with experience of Scots law would no longer be appointed to the UK Supreme Court, but serving Supreme Court justices with experience of Scots law should continue to sit until they retire.

If Scotland secedes from the UK, as the law stands peers who live in Scotland would have to pay tax in the rest of the UK in order to remain as members of the House of Lords. If they did not want to do so they would have to retire from the House.

SNP MP Angus MacNeil said the House of Lords was an "undemocratic anachronism stuffed to the gunwales with over 800 peers of the realm who answer to no electors and are often there because of privilege or patronage".

He added: "To be lectured by them about timetables and for democratic processes is something that could only happen in Westminster.

"It will be elected representatives who will lead Scotland's transition to independence - not some elite club whose members can still turn up for just half an hour's work and get a £300 daily allowance."

The SNP has a long-standing position of not nominating members to the House of Lords.

Speaking as he continued his two-day trip to Scotland, Prime Minister David Cameron said he did not want to "get into timetables and what-ifs."

Mr Cameron told BBC Radio's Good Morning Scotland programme that he would "stick absolutely" to the terms of the Edinburgh Agreement, which commits both the UK and Scottish governments to respecting the outcome of the referendum.

He added: "We have always said there is no pre-negotiation. Let's settle this question about whether Scotland stays within the United Kingdom or separates itself from the United Kingdom."