AN MP has vowed to keep fighting to ban unpaid work trials after a government minister talked out his private member's bill.

Stewart McDonald said he had been promised that moves to change the law and protect jobseekers would not be prevented from progressing in this way.

Following the Commons session, he tweeted: "After assuring me that the government would not talk out my Bill they have now done so. The Unpaid Trial Work Periods (prohibition) Bill is dead but the campaign to change the law continues."

He added that he would ask HMRC to "look into the arrangements" of Andrew Griffiths, Minister for Small Business, Consumers and Corporate Responsibility, after an advert emerged for an unpaid internship within his constituency office.

The ad, dated 2012, promised expenses for travel and food.

Griffiths, who killed off the bill, said he had "never, ever had an unpaid internship" in his office and later clarified, via a point of order, that the position had been advertised but not filled.

Amid questions on whether the law-change would apply to work experience or taster sessions in a work environment, Griffiths said: "As it's drafted, this Bill would exclude those kinds of things – anything from making the coffee briefly would be outlawed.

"The Bill sets the threshold at zero, so any moment spent working would be caught up within this Bill."

However, McDonald told MPs that unpaid trials hit "the lowest paid and the lowest skilled in our economy" and that those affected "either don't know their rights and can't stand up for them," or fear losing paid employment.

The Glasgow South MP said he would never again shop in bargain store B&M after learning that a young man with autism had been "stacking shelves for three or four days" before being sent away with no pay, and that supermarket chain Aldi advertised for 150 unpaid trial shifts when opening a new store in the north east of Scotland.

Aidrie and Shotts MP Neil Gray stated that those "exploited" include those with learning disabilities who are "are desperate for work and see these as their only opportunity".

But, talking out the Bill, Griffiths said no new regulation was needed, stating: "What is clear is that the law is already very, very clear on this point."