Today, around one in eight men work part-time, compared to fewer than one in 12 in 1997. This part-time work tends to be associated with lower pay, while higher paid men work more.

Resolution Foundation labelled it as a “hollowing out”, with men increasingly polarised into the top and bottom rungs of the workforce.

The study – Counting the Hours – found that the share of men earning less than £175 a week has increased by 70% over the last 20 years, while the share of higher-paid men earning more than £1,060 has increased by 15%. The ‘middle’ has decreased by 15%.

In spite of concern over longer working hours, average hours for the highly paid have only increased by half an hour each week.

Stephen Clarke, analyst at the Resolution Foundation, said: “When people talk about the labour market ‘hollowing out’ they’re normally referring to mid-skilled jobs moving to other parts of the world, or disappearing altogether as a result of automation.

“But Britain’s real hollowing out problem has much more to do with the hours people are working than the rates of pay different jobs bring.

“The increase in earnings inequality among men is about the increasing number of low-paid men who are either reducing their hours or moving into part-time work, in some cases against their wishes.”