PAY caps should be introduced for "greedy and self-centred" private sector executives and the SNP should go into the next Holyrood election on a platform of raising taxes, one of the party's backbenchers has said.

John Mason, the Glasgow Shettleston MSP, made the case for his party to advocate a radical redistribution of wealth at a fringe event on the first day of his party's conference, as he claimed the free market "is not working" and that the SNP and Scottish Parliament had a responsibility to ensure "things are shared out more fairly."

Discussing whether the SNP should go into next May's election proposing using to use new powers to raise taxes, he admitted he was "leaning that way, but I suspect a lot of other people aren't."

Mr Mason's comments came on the day that a new opinion poll was published showing that nearly 60 per cent of people do not believe Holyrood should use new income tax powers, due to come into force in 2017/18, to increase the levy to pay for a more generous welfare state. However, 52 per cent would back tax rises if the proceeds paid for better public services, the YouGov survey found.

The comments drew a strong response from David Watt, of the Institute of Directors, who said the nationalists would pay the price at the ballot box for suggesting tax rises and added that the vast majority of his members were paid relatively modest salaries of around £70,000 meaning excessive fat cat pay was not a significant issue north of the border.

But Mr Mason, who admitted he had formerly been sceptical about the idea of pay caps, said he had been won over by the idea after becoming convinced that more equal societies perform better and said he was hoping to persuade his party to take a new approach.

He said: "The emphasis within the party has been to help people at the bottom, and help them move up. I personally, and the party hasn't quite got there yet, feel that it's not just going to be about helping people at the bottom. We also do need to look at what is happening at the top.

"Clearly, we're going to have to take some drastic action because at the moment, things are not happening. I feel that high pay is not victimless. If someone gets high pay then there are victims going along with that, other people are either not getting paid properly or not a job at all when they could be sharing some of that wealth.

"In an ideal world, people would just not be as greedy and as self-centred as some clearly are. In practice that's not going to happen. I'm increasingly convinced that there needs to be some kind of cap on top wages and some kind of limits on top wages.

"The arguments against that tend to be we need the best people to run our company, or city council, or whatever. Let's look at the practicalities of that. Was it the best people running the banks in 2008?Clearly not. Was it the best folks running Volkswagen in 2015? Clearly not."

The fringe event was organised by the High Pay Centre, a think tank which recently published research showing that 35 executives at Scotland's top companies shared a combined pay bonanza of £55 million in 2014 and is campaigning for pay differences between the highest and lowest paid workers to be reduced.

Mr Watt said that he was not in favour of low rates of pay, but warned that the idea that all of his members were "fat cats" was "very far from the truth."

He added: "I do worry about legislation, because much of legislation has unintended consequences. You could change the ratios by employing less people. As far as executive pay is concerned, let's keep it sensible. It's not a massive problem in Scotland."