Britain's top bosses are earning 143 times their average employee's wage, a report has revealed, amid growing anger over inequality and CEO pay.
The figure marks a rise from 1998, when the average CEO was paid 47 times as much as his or her workers, according to the High Pay Centre, a U.K. think tank.
Mining firm Randgold Resources was shown to have the widest pay gap, with CEO Mark Bristow earning £4.4 million ($7.36 million), or 1,498 the salary of the average worker at the company.
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This was followed by Martin Sorrell's WPP who is paid a staggering £29.8 million, or 780 times his average employee.
British American Tobacco, SAB Miller and Unilever are among the top 10 FTSE 100 companies with the largest pay gaps.
"While Government figures confirm that wages for ordinary workers keep falling, it's clear that not everyone is feeling the pain," High Pay Centre Director Deborah Hargreaves, said in a press release.
"When bosses make hundreds of times as much money as the rest of the workforce, it creates a deep sense of unfairness."
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The report comes amid a fierce debate over inequality and CEO pay. The U.K government has brought in measures in an attempt to curb executive pay such as forcing companies to report a single figure on how much the CEO earns in an attempt to be transparent. Shareholders have also been given a binding vote on directors' remuneration packages.
The High Pay Centre found the CEO pay figures from the companies' financial reports, while average worker earnings at the FTSE 100 firms were provided by Pensions and Investment Research Consultants (PIRC).
The pay gap ratios are calculated by taking account of the salary of CEOs and employees at FTSE 100 companies only. If the chief executives' pay packet was compared with the whole of the country it would be 174 times the average U.K. worker.
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"Britain's executives haven't got so much better over the past two decades. The only reason why their pay has increased so rapidly compared to their employees is that they are able to get away with it," Hargreaves added.
- By CNBC's Arjun Kharpal