A union boss has accused a drinks firm proposing to axe 900 whisky jobs of being "drunk on greed".

Earlier this month, Diageo announced plans to close its Johnnie Walker bottling plant at Kilmarnock and the Port Dundas grain distillery in Glasgow. A total of 700 jobs could be lost at the Kilmarnock plant alone, with a protest march and rally taking place in the town on Sunday.

First Minister Alex Salmond will speak out at the rally against the company's plans, as will Kilmarnock and Loudoun MP and former Scottish Secretary Des Browne.

The demonstration, which was expected to attract thousands of people, will also hear from Unite assistant general secretary Len McCluskey, who is set to claim that Diageo's proposals are driven by greed.

The union chief will say: "These are job cuts driven by one thing only - greed. This is a company drunk on greed. It is making mega-profits - more than £2 billion last year - and wants still more."

But he will add: "We have news for Diageo and its boardroom - the days of 'greed is good' are over. Unite is not going to accept that these jobs are going.

"If this company thinks they can throw hundreds of decent working men and women on the dole without a fight to the end, then they have been partaking of too much of their merchandise."

Mr McCluskey will tell Diageo it is "time to sober up" and he will pledge the union will not stand by while the firm "destroy communities and shut plants which are efficient and profitable".

Liberal Democrat MSP Ross Finnie will also take part in the protest, as will Tory leader Annabel Goldie and fellow Conservative MSPs John Scott and Margaret Mitchell.

However Andrew Morgan, the president of Diageo Europe, has already said the decision to close the Kilmarnock bottling plant was thought to be the best option for the company. Diageo has also said it will "offset" the cuts with 400 new jobs at its Fife packaging plant.

As well as the Fife expansion, the drinks firm has said a coopering centre will be created in Clackmannanshire. It has also stated there will be no compulsory redundancies at sites for one year.