The Government has come under fire for suggestions it wants to scrap the Working Time Directive, the EU rule which restricts the working week to 48 hours and protects other employment rights.
But after a hailstorm of criticism from unions and the Labour Party, Theresa May refused to explicitly rule out abolishing the Working Time Directive (WTD).
The directive has for years been derided by Tory eurosceptics who argue it hiders economic growth and places a particular burden on the NHS.
Here are 11 pro-Brexit Conservatives who have indicated the WTD should go.
Michael Gove is reportedly leading calls to scrap the WTD, which has always been loathed by fellow Tory Brexiteers.
A source told the Sun on Sunday: “This is what taking back control is all about.
"It will put the power to decide how hard to work back into the hands of the people who matter - the ordinary British worker."
“One or two Brexiteers have been pushing to scrap this daft directive and there is big support for it in Cabinet.”
The then-London mayor blasted the WTD in a report in 2014 where he argued life outside the EU could be "attractive".
He wrote: "There is little doubt that it is that extra stuff, the stuff from Brussels, that is helping to fur the arteries to the point of sclerosis.
"The weight of employment regulation is now back-breaking: the collective redundancies directive, the atypical workers directive, the working time directive and a thousand more."
Last year he complained about the European Court of Justice determining that the UK had abide by the WTD, despite its opt-out of the social chapter in a speech on the EU being a "failed state".
The International Development Secretary said during the Brexit campaign that there would be benefits to slashing the “burden” of EU employment legislation
She said: “If we could just halve the burdens of the EU social and employment legislation we could deliver a £4.3 billion boost to our economy and 60,000 new jobs.”
In 2007, he wrote a report calling for Brussles working time regulations to be repealed as part of a package of measures to cut £14bn in red tape.
Anti-EU backbencher brought forward legislation, the Working Time Directive (Limitation) Bill, as he railed against the "absurdity of doctors and other health professionals having to work rigid hours, and therefore not being able to do the best for their patients".
Theresa May's Brexit minister in the House of Lords - previously a Conservative MEP - expressed his desire to abolish the whole employment and social affairs directorate during a debate in the European Parliament in 2012.
"Surely one of the best ways for the EU to speed up growth is to scrap the employment and social affairs directorate in the commission, and repatriate its responsibilities to national governments," he said.
"Then we could scrap the working time directive, the agency workers’ directive, the pregnant workers' directive and all the other barriers to actually employing people.”
Hannah Mckay / Reuters
In the House of Commons in 2012, the now-Leader of the House said: “I urge the Government to look carefully at scrapping the entire burden of regulation on micro-businesses with, say, three employees or fewer.
"I envisage there being absolutely no regulation whatsoever - no minimum wage, no maternity or paternity rights, no unfair dismissal rights, no pension rights - for the smallest companies that are trying to get off the ground."
Supported the Working Time Directive (Limitation) Bill - along with fellow hard Brexiteers Peter Bone, Philip Davies, Sir Edward Leigh, David Nuttall and Philip Hollobone - which would have stopped the EU Working Time Directive from being effective in Britain.
Has claimed the WTD is a “
burden”. The International Trade Secretary wrote in the FT
: “Political objections must be overridden.
"It is too difficult to hire and fire, and too expensive to take on new employees
"It is intellectually unsustainable to believe that workplace rights should remain untouchable while output and employment are clearly cyclical.”
Iain Duncan Smith
During the referendum campaign, the former Conservative Party leader dodged questions on whether the UK would keep holiday and working hours rights under the WTD if it left the EU, saying it was best it was "flexible"