The data released by the High Pay Centre think tank reveals that the average FTSE 100 chief executive is paid 117 times more than the median worker, at £3.46m a year. By 5pm BST on January 6, bosses of the UK’s biggest companies will have hoovered up more than the £29,559 annual salary earned by the median full-time employee.

Tim Roache, the general secretary of the GMB, one of Britain’s largest unions, branded the FTSE 100 CEOs as “fat cats” and hit out at the figures as “a source of national shame.”

Frances O’Grady, general secretary of the TUC, which represents the majority of trade unions, insisted that the huge gap between the top and average earners in UK firms “tells you everything about how unfair our economy is.” O’Grady wants to see workers on pay committees and company boards to keep a check on the high salaries of top bosses.

The pay gap issue between company bosses and workers has rumbled on over many years and is one that successive UK governments have failed to even acknowledge through policy, until now. Over the next few months, individual businesses with more than 250 staff will have to publish pay ratios between top earners and the rest of their staff in annual reports for the first time.