BBC's Jonty Bloom: "The unions know they must lobby as hard as business to get what they want"

The congresss will be asked to endorse demands that parents of children under five should be entitled to 13 weeks paid leave.

Legislation due to come in later this year provides only unpaid leave for workers with children.

The TUC's expected move on the final day of speeches comes after Prime Minister Tony Blair told delegates to lobby as hard as business for the changes they want.

Mr Blair told delegates: "For the first time in 20 years, trade union leaders came into Downing Street; they are consulted, they are listened to, just as the CBI are.

"No favours, but fairness. Equality. What we promised."

A consultation process on leave entitlement for workers was launched at the start of August by Trade and Industry Secretary Stephen Byers.

Mr Byers said the laws would, for the first time, give fathers the legal right to time off when their children are born, and that parents could take up to 13 weeks unpaid leave while their children are under five.

British industry complained at the time that the changes would introduce too much red tape.

Correspondents say business is again likely to fight hard to convince the government that it would be unable to afford the unions' latest call for paid leave.

'Speak up for the poor'

The final day of the Congress is also due to hear debates on sex equality and disability issues.

Listen to Baroness Margaret Jay's introduction to the debate on equal rights

Unions are also expected to be urged to reach out to the poorest people of the world in a speech by International Development Secretary Clare Short.

The minister was due to call on the TUC to work in partnership with the government and business to lift people out of poverty wherever they live.