Parents who refuse to pay child support could face jail, fines, or even the loss of their driving licence, under new legislation.

The Pensions and Social Security Bill will do away with the current complicated system of calculating child support rates.

Social Security Secretary Alistair Darling said the old system - which he said had "failed children" - would be replaced with a fairer, faster and simpler one.

He said: "Where someone deliberately delays in paying money to their children, then we will impose a new penalty of a charge of up to 25% of the money due until they actually pay it.

"We are also taking powers to make a temporary arrangement where there is difficulty in getting information from people."

Mr Darling added: "As a last resort, if somebody will not pay, if they will not co-operate, then the courts will be given the power, not only to imprison people, but if necessary, to remove their driving licence."

He said that of the 1.5 million youngsters on the Child Support Agency's books, only 100,000 had received all the money they were due.

A further 200,000 had received some money, but not all.

He said: "Under the new system, mothers and their children will get what they're due and quickly.

"Decisions will be made within days of an application rather than within months.

New computer system

"Money will get faster flowing and everyone will know where they stand."

Mr Darling said he was anxious to introduce the new reforms as soon as possible, but only once a new computer system had been put in place at the CSA.

He also outlined plans to make sure that maintenance money was chased up more effectively, including looking at the tax records of self-employed parents, and hiring specialist inspectors to gather information from employers.

The plans, however, have came under attack from Tories and groups opposed to the CSA.

Tim Boswell, Conservative MP for Daventry, said proposals to remove driving licences could breach European human rights legislation.

He said: "I would not give the government a chance of winning a case brought on that matter, where a plaintiff could say: 'I was a driver, I was entitled to drive, I was a safe driver and for some entirely different matter they took away our rights'."

The National Association for Child Support Action told BBC News Online the new measures "did nothing" to help children, and that threatening parents with prison and driving licence removal was "ridiculous beyond belief".

Spokesman Neale Sheldon said: "No-one is disputing that child maintenance, wherever possible, should be paid.

"But the CSA is not the way to go about it. It has a history of targeting soft options and bullying mums into filling in the forms.

"These new measures do not improve the situation at all, and could mean that fathers from the poorly paid jobs could end up worse off."

NACSA offers a 24-hour helpline on CSA issues, on 01782 646646, and can be contacted at PO Box 3159, Milton Keynes, MK6 2YB.