Bosses at Britain's biggest companies saw their pay rise by 16 per cent last year, despite ordinary workers' wages being outstripped by inflation.
CEOs of firms on the FTSE 100 enjoyed a salary bump of around £500,000 in 2022, according to the High Pay Centre.
The unions said it demonstrated that Britain has become a land of grotesque extremes, with well-off company chiefs benefiting from pay rises while hard-pressed families struggle during the cost of living crisis.
The gap between top bosses and top workers increased further in the year, with the median CEO paying 118 times the median UK full-time worker in 2022, up from 108 times in 2021.
Median salary for a FTSE 100 CEO rose from £3.38m in 2021 to £3.91m in 2022, the High Pay Centre said. It represents a upward trend after it dropped to £2.46m in 2020 after companies were hit by the Covid pandemic.
Pascal Soriot, chief executive of pharmaceutical firm AstraZeneca, was the highest-earning FTSE 100 chief executive, with a salary of £15.3m for the year.
BAE Systems' chief executive, Charles Woodburn, made his second highest salary, earning £10.7m. Albert Manifold, the head of building company CRH, was third with £10.4m.
Other highly paid bosses in 2022 - the year in which the energy crisis saw gas and electricity bills skyrocket - included Bernard Looney of BP, who made £10m and Ben van Beurden of Shell, who rake in £9.7m.
The High Pay Centre wants companies to include a minimum of two elected workforce representatives on the remuneration committees that set executive pay.
A model that prioritises a half-a-million-pound pay rise for executives who are already multi-millionaires is surely going wrong somewhere, said Luke Hildyard, head of the High Pay Centre.
The campaigner said that living standards were not being met.
After official figures show that average wages are still growing behind rising costs of living, despite progress in tackling price rises, the report comes a week after official figures showed that average wages are still rising.
The Office for National Statistics said that regular pay growth, which includes bonuses, reached 7.8 per cent over the three months to June compared to a year earlier, but actually dropped by 0.6 per cent once inflation was taken into account.
Labour said the economy is stuck in a low-growth trap under Tories, as its analysis of the latest economic forecasts suggests that UK growth will be the slowest in the G7 in 2024.
The Bank of England's August Monetary Policy Report suggests that economic growth is expected to be weaker than previously expected, downgraded from 0.75 per cent to 0.5 per cent.
Labour said this meant the UK would experience the slowest growth among the G7 group of countries, with shadow Treasury minister Tulip Siddiq warning low growth would now be a 'hallmark' of Rishi Sunak's premiership.
Since 2010, the UK has grown faster than France, Japan and Italy, and we are determined to meet the prime minister's pledge to grow the economy further while halving inflation - something Labour has no plan to do.