Workers should be granted the legal right to take paid time off so that they can train in order to ease the UK's skills shortage, the TUC has said.
UK workers often have to compete against better trained foreign rivals
The trade union body said long hours, and a lack of support from managers and the government meant UK workers were lagging in the global skills race.
Workers without formal qualifications needed most time off to train, a TUC survey of 840 union officials found.
The government said it had schemes in place to help boost workers' skills.
The TUC argued that a law change was necessary if UK workers were to improve their skills and compete better in the global market.
"We need new legal rights to paid time-off to train," Liz Smith, director of the TUC's Unionlearn organisation, said.
"Such rights are especially important for those without a qualification at the standard expected of school leavers."
A spokesman for the Department of Education and Science said that efforts were being made to boost workplace skills.
"That is why the national employer training programme Train to Gain launched this year means individuals are released by employers to undertake the training they need," he explained.
"Demand for this programme is already extremely high with over 10,000 employers signed up and more than 50,000 learners engaged in learning activity," the spokesman said.