British trade unions have taken their campaign against sweatshop labour to the Olympic city of Athens.

The TUC was in Greece on Tuesday to publicise its call for the International Olympic Committee (IOC) to ensure that sportswear carrying the five ring logo, a $1.5 billion industry, is not made by exploiting staff.

A report released by the TUC and Oxfam earlier this year found that many manufacturers pay "inadequate wages", enforce compulsory overtime and deny workers' rights.

While four British companies have given assurances have given undertakings that they will not act unethically, the IOC has so far refused to use the power it has over the trademarking of its logo to get tough with unscrupulous employers.

With the Athens Games set to begin this week TUC general secretary, Brendan Barber, said was the time is right for the governing body to take a stand.

"The Olympics is a showcase of endeavour and achievement," he said.

"But the hidden heroes of this festival of human spirit are the millions of workers in sportswear sweatshops.

"A number of major sportswear companies and national Olympic bodies have engaged with our efforts to bring the abuse of sportswear workers to an end.

"We urge the IOC to reconsider their position and support our campaign and the values it champions."