A Tory minister said he understood what it was like to live on a zero-hours contract because he once worked as a barrister, charging £250 per hour.

During a 2013 parliamentary debate about the problem of insecure work, Guy Opperman said: “It is right that we debate issues of low pay and the nature of contracts in this House.

“I should make a declaration, Mr Speaker, that as a former barrister I was unquestionably on a zero-hours contract in that I was an employee not obliged to be given work by my employer and in that particular circumstance I had to accept though.”

He went on to defend the controversial contracts, which do not guarantee any work. Zero-hours contracts “help to plug a gap”, Mr Opperman said, adding that MPs should not criticise councils who have employed workers in this way.

In her reshuffle this week, Prime Minister Theresa May promoted the MP to a junior role in the Department for Work and Pensions.

During the 2013 exchange, Labour MP Alison McGovern asked Mr Opperman to consider the reality of working on a contract that did not guarantee hours “perhaps not in his own life, but in reality, in our economy now.”

Mr Opperman replied: “As a barrister, I spent two and a half years without a contract. With respect, I therefore suggest I do have some experience of that, with no contract whatsoever.”

Almost 1 million people now rely on a job that does not give them any fixed hours for their main source of income, leaving many without the security of knowing they will be able to pay their bills.