The pensions regulator is expected to say that employers are not contributing enough to workers pensions following the implementation of the auto-enrolment scheme, which began in 2012.

Under the plan, employees, employers and the Government all pay into the pension pots of workers aged over 22 and earning over £9,440.

However, concerns have been raised that the contributions will still not be enough to cover employees when they reach retirement age.

"There is certainly a risk of disappointment, unless we can encourage people to put more money into their pensions. For now getting started is great, but it is only a start," said Tom McPhail, pensions expert at Hargreaves Lansdown.

"It is understandable that employers are just starting off with the minimum of contributions because their pension bill is going up. However, between them and their employees we need to get to a point where more money is going in, otherwise these employees are going to be disappointed when they do get to retirement."