British workers will no longer be able to work more than six hours without a break, after the government yesterday lost a battle over working hours in the European Court of Justice.
The court told the government that it was breaking the law by not forcing employers to make sure their staff took rest breaks between shifts.
The decision followed a case brought against Britain by the European Commission, which had accused the government of breaching Europe's working time directive, which limits the working week to a maximum of 48 hours.
Britain has an exemption that allows individuals to opt out of this maximum, but shift break rules still applied.
Britain is obliged to apply daily and weekly rest break rules, allowing for at least 11 hours between ending work one day and beginning the next, plus a weekend break of at least one day plus 11 hours.
Guidelines from the Department of Trade and Industry advise employers that they must ensure workers "can" take their rest, but do not force bosses to make sure employees took such breaks.
The court agreed with the commission that the government was encouraging "non-compliance" of these rules and that the existing guidelines were "meaningless".
In its ruling it said: "The (DTI) guidelines are liable to render the right of workers to daily and weekly rest periods meaningless because they do not oblige employers to ensure that workers actually take the minimum rest period, contrary to the aims of the working time directive."
What the ruling means in practice is that employers will have to ensure staff take off at least 11 hours between working days, and have a minimum of one day off a week, as well as a 20-minute rest after every six hours of work.
Business groups have in the past argued that such a regime would mean workers being would be unable to choose to work long hours to earn more money because they would be forced to take breaks against their will.
Brussels has argued the decision simply brings Britain into line with the rest of Europe.
The ruling is being seen as a significant victory for the European Commission, where Britain's opt-out of the working time directive remains an irritation, particularly for countries such as France and Germany, which worry Britain is getting an unfair competitive advantage.
The commission said of the ruling: "We need to have these rights or that would put us back into the 19th century."
It was also welcomed by unions. Brendan Barber, general secretary of the TUC, said: "Employers will now have to do their utmost to ensure their staff get the breaks they are entitled to. The government must now change its guidance on rest breaks to ensure that workers know their rights and can benefit from them, and that employers know their responsibilities and meet them fully."