The Leveson Report has questioned Alex Salmond's insistence he was duty bound to lobby UK ministers to back Rupert Murdoch's proposed £8 billion BSkyB takeover.

The First Minister had said he was obliged to make the case to the Coalition Government because of the potential boost to Scottish jobs. But that view was challenged by the report into press ethics.

It found that the jobs issue was "irrelevant" to the decision ministers were making. If they had been swayed by the argument their ruling could have been "illegal".

Lord Justice Leveson added he had "absolutely no doubt" Mr Salmond was motivated by a desire to help Scottish employment which he said was "entirely laudable" and the "proper function of the First Minister".

But he added: "How far that should be taken, however, is another matter."

The First minister's spokesman said the report was a "complete vindication of the First Minister's position in terms of the case he was prepared to put to promote Scottish jobs".

Scottish Labour parliamentary business manager Paul Martin said the report "gives a fascinating insight into the murky way Alex Salmond goes about his business".