Burton MP Andrew Griffiths has come under fire in the House of Commons during a debate about fair pay for "trial period" workers - after it emerged he had once posted an advert for an unpaid intern.

SNP MP Stewart Malcolm McDonald called out Tory Mr Griffiths, the Government's new Small Business Minister, during the debate for advertising an unpaid intern role in 2012.

The advert was for a "constituency intern" to work in the MP's Burton office. It said that "expenses such as travel and food" would be covered.

Mr Griffiths said he decided not to fill the position, but went on to tell the House he had appointed a researcher after they had completed unpaid work experience for him.

An unpaid intern job advertised by the office of Burton and Uttoxeter Andrew Griffiths in 2012
An unpaid intern job advertised by the office of Burton and Uttoxeter Andrew Griffiths in 2012, which was not filled

It came as backbench MP Mr McDonald failed in his bid to get a bill passed securing the national minimum wage for those working on a "trial period" basis.

He told the Commons: "I know the Minister [Mr Griffiths] believes that the law covers trial shifts and unpaid internships.

"He said to me 'Stewart, we have no wish to derail your Bill, but we think the law covers it already'.

"Let us split that proposition, because those two things cannot sit comfortably together.

"If the law as it stands covers this - if the Minister listens, I can educate him - there is a problem for the Minister, because I have found on the w4mp website an unpaid internship from 2012 in his office for three to six months.

"If it is the case that the law as it stands bans unpaid shifts and unpaid internships, either he has to refer himself to HMRC, or I am afraid I will have to do it for him."

In response, Mr Griffiths told the Commons the bill was not needed because existing law already prohibited unpaid trial periods.

He also said of the constituency intern advert: "I can confirm that that position was never filled; it was advertised, but never filled.

"I am, however, reminded that a paid researcher worked for me for, I think, a brief 20 days of internship with travel expenses paid before she took on the role as a full-paid researcher.

"It was so brief that it had slipped my mind, but I apologise if I misled the House in any way."

Burton and Uttoxeter MP Andrew Griffiths has praised the UK's export economy
Burton and Uttoxeter MP Andrew Griffiths

Speaking after the debate, Mr Griffiths said: "I’m always keen to give young people an experience and flavour of Parliament.

"That’s why I gave work experience one day a week for a few weeks.

"They were already working four days a week with a charity and wanted to better understand how Parliament works.

"Having got that experience of Parliament, when an opportunity arose in my office, I was delighted to be able to offer them a paid full time job.

"This kind of work experience can be a real help and as shown in this case, can help young people get into what can be a competitive work environment in Parliament.

"They weren’t doing Parliamentary work, but more learning the processes and how research works in the political environment.

"I also regularly have work experience people from local schools, colleges and students at university so they can experience what it is like to be in Parliament."

The debate over the proposed Unpaid Trial Work Periods (Prohibition) Bill took place on Friday, March 16.

The bill failed because the debate passed a controversial Parliamentary time threshold. It means that if a backbench bill is still being debated at 2.30pm on a Friday, it cannot become law.