PARENTS across the Bristol region are owed more than £55 million in child maintenance payments, it has been revealed.

The huge backlog is the result of a system for recovering money that ministers say is "completely dysfunctional".

Ministry of Justice figures show more than one in five parents using the Child Support Agency are still not receiving regular payments.

It comes as the government's latest attempts to reform the much-criticised system return to the House of Commons.

Last week a proposal to charge single parents for using the CSA suffered a heavy defeat in the House of Lords, by a majority of 142. Conservatives and Liberal Democrats joined Labour peers to table an amendment that would have spared many single parents from the charge.

But Work and Pensions Secretary Ian Duncan Smith has vowed to overturn the amendment and defended the up front charge of up to £100, saying: "we're not asking for much".

The figures showed a backlog, dating back 15 years since the CSA was set up, of £21.9million in the Bristol City Council area. There are arrears of £14.2 million in South Gloucestershire, £11.2 million in North Somerset and £8 million in Bath and North East Somerset.

Officials at the ministry insisted the amounts had not been written off. But just £1.5 million of all the payments collected across the four council areas last year related to the arrears. And one in five parents are not receiving regular payments. In Bath and North East Somerset the figure was 23 per cent.

The government wants to reduce the number of parents turning to the CSA for maintenance arrangements, urging separating partners to talk through the arrangements first.

But campaigners say the charge would "make children pay" for repairing the system.

Almost £19 million changed hands between parents through the CSA across the four areas last year.

But Work and Pensions Minister Maria Miller said every pound recovered in payments cost 40p in administration costs. Each case could cost taxpayers up to £40,000, she said.

She added: "It's right families who are struggling financially after separation get support. It's not right that the public pays twice; our reforms are fair."