Future increases in the national minimum wage threshold should be tied to a sustained increase in productivity, according to a new report by an HR group.

Earlier in March the Low Pay Commission (LPC) recommended a three per cent increase in the adult rate of the wage; increasing it by 19p to £6.50 per hour.

The Chartered Institute of Personnel and Development (CIPD) said this would help to restore the value of the low pay threshold without putting pressure on employers.

But it added that rises in coming years should only happen if UK employers can create a sustained increase in productivity from employees.

Government data shows that UK output per hour worked is 21 per cent below the average for the world’s most developed nations.

It means the country’s productivity gap is the widest in 20 years; something which analysts blame for the recent drop in real income growth.

CIPD chief economist Mark Beatson said: “We expect to see further real terms increases in the NMW in the coming years to make good the value lost. However, this relies on productivity growth – real wages can’t rise sustainably without it.

“Ultimately, real progress on low pay relies on encouraging employers to invest more in training and career progression opportunities so the lowest paid workers can lift themselves out of minimum wage roles and add greater value to the firms that employ them.

“The UK performs poorly compared to other developed nations on both the sheer number of low paid roles and the opportunities for those in them to grow and develop in their roles.”