Ms Roberts has been trying to get child support for seven years

Caerphilly MP Wayne David said he has received a wave of complaints from constituents about the Child Support Agency (CSA) - which collects payments from absent parents.

Mr David was one of a group of MPs who met the Work and Pensions Minister Chris Pond on Tuesday.

He said payment delays of up to seven years were "totally unacceptable".

One of Mr David's constituents, Sandra Roberts, has been trying to get child support to help bring up her 14-year-old son Daniel since her ex-husband went self-employed seven years ago.

"They don't get back to you when I phone, I can't seem to get answers to specific questions when I write," she said.

"It goes round in circles, I don't get anywhere, and the years roll by."

Mr David said he was "hopeful" after the meeting

Elizabeth Danter, from Cardiff, who has twin 15-year-old girls, says she is owed �3,500 and is looking for another job to supplement her income.

She added: "The CSA's new system just isn't workable.

"I make telephone calls and can't get through - it's a nightmare.

"And even with the complaints I've made via my local MP, as well as through the CSA, I just feel I'm at a standstill."

Mr David said such delays were "totally unacceptable".

He added: "What is even worse is that case is not the exception - I have got many similar cases like that, and MPs have other cases. "

He said that computer failures were being blamed because a new �427m system that was introduced around five years ago had failed to work "from the start".

In Westminster last November, Chris Pond said he would look into the problem, but Mr David said that action was needed.

"We want those computer problems sorted out and if it means massive investment by the government then that must happen," he said.

He also said it was "quite incredible" that the government had been reducing staffing in the CSA from 12,000 to 8,000 in recent years.

After the meeting, he said he was "hopeful" there would be progress.

He added: "I don't think there'll be any immediate solution, but nevertheless over a period of weeks, rather than months, we'll see some sort of progress.

"And that's a step forward because many people have been waiting four, five or even six years for this issue to be resolved."

The CSA said that it could not comment on individual cases but said that there had been difficulties obtaining money from self-employed absent fathers and also with computers.