Gordon Brown hinted workers might be given the rights, but Brian Binley, Conservative MP for Northampton South, said the plan had been put in place merely to "look good" for the trade unions, a major funder of the Labour party.

He said: "If you have got five or six people in a company and somebody goes on maternity leave for six months, it's a big blow.

"There is a lot of global challenge in the business world. The last thing we need to do is put pressure on small businesses.

"The truth of the matter is that many businesses do know that it's used as an excuse and it puts another cost on businesses. It's not easy to control."

Mr Binley added businesses need to be supported during the credit crunch.

Many companies and organisations offer flexible working to staff. A spokesman for Barclaycard said: "Every department will have its own policy. As a general rule of thumb, Barclaycard offers flexible working as long as it fits with the demands of the job. People negotiate on an individual basis with their line manager."

A spokesman for Northamptonshire County Council said the authority had long recognised the benefits of flexible working.

He said: "County council managers embrace flexible working arrangements as part of their day to day responsibilities.

"Line managers take responsibility for discussing and agreeing the most effective way of delivering their services while ensuring that the needs of all parties are considered.

"As the county council strives for improvement through our people, our ability to react to change is enhanced through offering flexible working practices, to ensure that we have the right skills, in the right place at the right time."

Thomas Adams, of Oliver Adams bakery, said: "We have to be very flexible with our staff because we employ a great deal of women with families. The only way you have a happy workforce is if they're happy in their private lives."

He said staff could request time and the business accommodated them as far as possible, but the time was given off unpaid.