According to the GMB Union, Tomahawk Steakhouse called a Zoom meeting for all of its staff and asked them to sign an agreement to lend a tenth of their pay to cover pension and national insurance contributions.
Staff were told that if they didn’t sign the agreement, the company would “review whether you are suitable for your role,” the union said.
Workers at Tomahawk, which has venues in York, Newcastle, Durham and Hoxton in east London, then reportedly received a letter which included a loan agreement.
In the letter, which has been seen by the BBC, Tomahawk told staff that the company has a “short-term cash flow issue” and it now required the workers “help and support”.
It added: “We respectfully ask, in these difficult times, for you to support us by agreeing to pay your own Employers NIC/Pension Contributions by way of a voluntary ‘loan’ to the company, whilst we are in lockdown”.
A member of staff, who did not want to be named, told the BBC that Tomahawk should not be relying on its workers for funds when the restaurant chain recently opened a new site in London.
"They said if you don't sign it we will have to see if this job's right for you,” the worker said.
GMB Regional Secretary, Neil Derrick, accused Tomahawk of “bullying its own young, low-paid staff” to raise interest free cash.
“This is an outrageous abuse of the furlough scheme and a legal loophole that must be closed,” said Mr Derrick.
“This callous behaviour will leave waiting staff, pot-washers and cooks short of cash and force them to take out interest rated loans to cover the shortfall or face losing their jobs.
“Tomahawk needs to take a long hard look at its behaviour – and this legal loophole must be closed before other companies follow suit.”
Labour MP for York Central, Rachael Maskell, raised a written question to the Treasury Minister Jesse Norman about whether employers can ask furloughed staff to loan the business a proportion of their furlough payment.
Mr Norman said employers cannot enter any transaction with workers which reduced the wages below the amount claimed by the furlough scheme.
He said: “Employers are required to pay staff all the Coronavirus Job Retention Scheme (CJRS) grant they receive from HMRC to cover 80 per cent of wages up to £2,500 per month.
“The employer is still required to meet the employer’s National Insurance and pension contributions.”
The Standard has contacted Tomahawk for comment.