The British government faces the prospect of a major confrontation with employers after announcing proposals to give fathers up to six months unpaid paternity leave during the first year of their baby's life.
The plans to be contained in the forthcoming Work and Families Bill could see 400,000 men qualify for leave each year.
Proposals floated last year for mothers to take the first six months as paid maternity leave leaving the two parents to share the remaining six months have been dropped as unworkable.
At present, new fathers are legally allowed two weeks' leave and receive £106 a week in statutory paternity pay.
The Bill will also see an extension of maternity rights, with paid maternity leave for new mothers being extended to nine months' from April 2007 and a year from 2009.
But while the proposals would British fathers some of most generous paternity rights in the world, it seems unlikely that many of them will be queuing up to claim them.
Currently, only one in five new fathers take their full two weeks paternity leave and without any financial support from the government for the proposed six months leave, it will be economically impossible for most families to survive without a father's income.
Moreover, most men will be unwilling to risk their career prospects by taking up a right seen as one step too far by their employers.
Employers will be further angered by the fact that having potentially lost a key employee for six months, they can then be taken to an industrial tribunal if they are unwilling Ė or unable Ė to give them back their previous job.
BCC director general David Frost said: "The issue for businesses is that plans to extend parental leave could not only be an administrative nightmare, but could leave firms without key staff for long periods of time.
"While employers want to actively support flexible working, the Government must realise that extending parental leave at such an unprecedented rate will add more confusion and pressure to firms who are already struggling to compete."
The CBI's deputy director general John Cridland said: "This will put a lot of pressure on business and we have huge concerns.
"The new right for fathers is very different from shared maternity leave which was a better option for business".