Working parents are to be granted the right to request time off work to care for their children, under new legal guidelines to be announced this week.

Trade and industry secretary Patricia Hewitt will set out the "family friendly" policy on Tuesday alongside a report from the government's work and parents taskforce.

For the first time under the new guidelines fathers will get legal protection for seeking shorter working hours after childbirth and working mothers will get more rights under a statutory code of practice to help parents balance work with family life.

But, as widely predicted, the measures fall short of giving parents the right to insist on time off and employers can refuse requests if they give written reasons that it damages their business.

Companies are to be monitored on the guidelines by government and employees can take their boss to an employment tribunal if the code of practice is breached.

The "right to ask" will disappoint family campaigners seeking a failsafe guarantee that working parents could go part-time.

There are also concerns that the new guidelines will only apply to the parents of pre-school children, limiting the scope of the measures as less than half the mothers of under-fives are in employment.

The TUC will welcome announcement "but will continue to campaign for stronger and better rights for working parents".