Peers have warned that Angela Rayner’s plan to allow Britons an automatic right to ‘flexible working’ could risk national security. The Deputy Prime Minister’s Workers' Rights Bill will give staff the powers to demand flexible working arrangements, including working from home or working just four days a week.

The flagship Bill will restrict firms’ ability to decline the request, making them prove why such a demand is not feasible. The legislation, currently working its way through the House of Lords, has now been condemned for risking national security. Tory peer Lord Sharpe of Epson has demanded a carve out for Britain’s security services, warning that without an exemption spooks could drop the ball.

He warns: “The need for immediate action, tight schedules and often secretive operations simply cannot be fully compatible with the predictability that flexible working arrangements might demand.”

“It’s essential that we avoid unintended consequences of applying the Bill’s flexible working provisions to the intelligence services.”

He argued that security service jobs involve “highly sensitive operations often conducted in real-time and under exceptionally stringent conditions. They work to protect the nation from terrorism, espionage and cyber attacks, amongst other threats”.

“The national security landscape is dynamic and fast-moving and requires the utmost flexibility, discretion and responsiveness from their employees.”

The Tories have also warned that the Bill as a whole will clobber businesses with burdensome costs that will hit economic growth.

In addition to the flexible working provisions, the workers rights legislation also promises a crackdown on zero-hour contracts, wider eligibility for sick pay, and full employment rights from day one of working including protection from unfair dismissal.

Baroness Meyer has also warned that the Bill puts the UK at risk of “being held to ransom” by trade unions, and a return to the “economic chaos of the 1970s”.

A government spokesman said: “Through our transformative Plan for Change, this Government has delivered the biggest upgrade to workers’ rights in a generation, and our measures already have strong support amongst business and the public.

“We’ve consulted extensively with business on our proposals, and we will engage on the implementation of legislation to ensure it works for employers and workers alike.”