There has been concern that a new court could threaten Scots law

Justice minister Cathy Jamieson said the proposed court would respect "the unique nature" of the Scottish justice system.

In its formal response to the proposals, the Scottish Executive told the newly-created Department of Constitutional Affairs it "welcomed" the plan.

The proposal for a supreme court forms part of wider constitutional changes which include the scrapping of the post of Lord Chancellor.

At present, criminal appeals are heard in Scotland but the appellate committee of the House of Lords is the ultimate court of appeal for civil cases in Scotland.

Under the changes, the supreme court would take over this function for civil appeals, and criminal appeals would continue to be heard in Scotland except for those cases that throw up "devolution issues".

We believe a supreme court for the whole of the UK will bring greater coherence to the system both north and south of the border Cathy Jamieson

As it was the Scotland Act - a piece of Westminster legislation - which incorporated the European human rights convention into Scottish law, some Scottish criminal appeals could raise issues which will now go to the supreme court.

Nationalists claim the reform is "a missed opportunity" and want all appeals to be heard in Scotland.

The Faculty of Advocates also warned the new supreme court could be illegal under the 1707 Act of Union unless the supreme court is completely separated from the Department of Constitutional Affairs.

But the executive submission voiced no such concern. It warns, however, that it is "essential" for the membership of the new court to include at least two people qualified in Scots law, and calls for statutory safeguards to enshrine this.

Ms Jamieson said it was an "opportunity" rather than a threat.

"Scotland is an integral part of the UK and this is an important step in devolving modern justice and constitutional systems with the right arrangements for Scotland's distinct laws and institutions," she added.