LABOUR has condemned a “mutual backscratching society” of bosses, as new figures reveal it would take an ordinary worker two lifetimes to earn the average pay of a FTSE 100 chief executive.

Britain’s average full-time wage is £28,213. But the figures, compiled by the High Pay Centre and the Chartered Institute of Personnel and Development, show that the bosses of the City’s top 100 firms are paid an average of £4.5 million — which is 160 times as much.

Labour’s shadow Cabinet Office minister Jon Trickett blasted: “Who decides what salaries they get? It seems to be people in very similar positions themselves. It’s a mutual back-scratching society.”

And GMB general secretary Tim Roache said: “We all know we live in a very unequal society — but these figures really bring home the scandalous gulf between the rich and the rest.

“Working people create the wealth in this country — and they are sick and tired of fat cat bosses getting all the cream, especially when everyone else suffers squeezed living standards.”

The average pay of FTSE 100 chiefs is actually down 17 per cent on 2015 — when the figure stood at £5.4m.

But it would take an average worker an astonishing 1,718 years to earn what advertising boss Sir Martin Sorrell received last year alone.

Today workers striking in three significant disputes — at London hospitals, at the Bank of England and at British Airways — will rally together in protest against pay restraint.

Mr Trickett told the Star: “These really low-paid workers are losing money to go on strike, while the people they work for are on astonishing amounts.”

Under the Tories public service workers have faced a 1 per cent cap on pay rises. Meanwhile, unions have accused the government of letting private-sector bosses off the hook by suspending enforcement action against those who illegally fail to pay the minimum wage.

Business minister Margot James said: “We have been very clear that to achieve this ambition businesses should be run responsibly, including ensuring executive pay is properly aligned to performance as outlined in the corporate governance reform green paper.

“This report shows encouraging signs that the UK’s largest firms are already making progress in this area and our responsible business reforms, which we will publish shortly, will help to enhance the public’s trust and confidence in big business.”

But High Pay Centre director Stefan Stern said the fall in executive pay was “welcome” but “so far, a one-off.”

He warned: “We need to see continued efforts to restrain and reverse excess at the top.”