WOMEN across the UK will no longer feel they have to choose between having a career and having children, Nick Clegg will insist today, as the Coalition publishes the final details of its landmark reform of parental leave.

While campaigners and some business groups give the changes a qualified welcome, the Institute of Directors brands them "a nightmare", warning that they will pile more burdens on already struggling businesses.

The policy to change parental leave is in the Coalition Agreement but it has caused major tensions between the Liberal Democrat and Conservative halves of the UK Government.

Consequently, the maximum parental leave will remain at 52 weeks while the ability to switch time off between parents will be limited to just three times, more if employees and employers can agree.

The reforms will extend parents' existing rights to request flexible working to all employees in an attempt to reflect the increased role of grandparents and other carers.

Under the new system the traditional 52 weeks of maternity leave, other than the first fortnight for a new mother's recovery, can be shared between the parents from April 2015.

But, in an effort to allay fears of the impact on smaller firms, bosses will have to agree any proposed pattern of time off and will retain the right to insist it be confined to a continuous block, with, after the first period of leave, no more than two subsequent changes.

Also, anyone taking total leave of six months or less over the period would be legally entitled to return to their same job.