Scottish first minister Alex Salmond described major supermarkets as the “barons of politics” after MSPs rejected proposals for a large retailer levy last week.

The proposals were voted down in the Scottish Parliament by 68 votes to 46, with Tory, Lib Dem and Labour MSPs describing the plan as “anti-competitive”. The levy would have brought in an extra £30m a year, with stores valued at more than £750,000 charged a 35% increase in business rates.

Asked on BBC Five Live why opposition parties - with the exception of the Greens - voted against the proposal, Salmond said: “My theory is that the supermarkets have the most enormous lobbying power. I think they are the barons of politics.”

Under the proposals, he said Sainsbury’s would have been asked to contribute an extra £2.5m a year, amounting to their revenue for a single hour. 

The minister hinted the plans would be included in the SNP’s manfesto ahead of the Scottish elections in May. “We can’t get it through this parliament, but I think it’d be a fair assumption ot say it’s something that we’ll take to the people,” he said.