The row came as Mr Alexander announced a £2million campaign to promote Loch Ness as a tourist destination.

The campaign, backed by tourism agency VisitBritain, will use the legend of the Loch Ness monster to advertise the area to overseas visitors and is expected to generate a £14million windfall.

The MP - whose constituency includes part of the loch - said it was "a jewel in the crown of the Highlands tourism industry".

In 2013, Labour attacked Mr Alexander for protecting his own constituency from Coalition spending cuts.

He was instrumental in delivering funding for a tourist railway, a bailout for the London-Scotland sleeper train and tax breaks for ski lifts, which helped operators in Aviemore.

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