The number of men doing part-time work because they cannot find a full-time job has more than doubled in the past four years, according to a study by the TUC.
The trade unions federation said almost 600,000 men were working part time in December while looking for full-time positions, compared with 293,000 at the end of 2007.
Latest official figures have shown that 1.4 million workers and self-employed people work part timebecause they cannot find full-time employment, the highest figure since records began in 1992.
People living in the East of England have been hit by the biggest increase in under-employment over the past four years, with the number of men "trapped" in part-time jobs more than trebling to almost 60,000, said the TUC.
Its analysis showed that the North-east, Northern Ireland and London also experienced sharp rises in involuntary part-time work. The number of women in involuntary part-time jobs has more than doubled in London and Northern Ireland over the past four years.