Labour have abstained on a Commons vote to give Holyrood the power to call a second independence referendum.

Last year Westminster 'lent' Scottish ministers the ability to hold the historic vote.

But David Cameron has repeatedly suggested that he would block another poll.

An SNP amendment to the Scotland Bill going through the Commons called for the power to be devolved.

It was defeated by the votes of Conservative MPs.

Labour sources said the party felt to vote against the amendment would have been to reject the current "partnership" between Scottish and UK ministers as set out in the Edinburgh Agreement which led to the independence referendum.