Claimants get very frustrated by the delays

Many of those applying for Child Tax Credit and Working Tax Credit who've been trying to contact the Inland Revenue via its helpline are still complaining about delays.

One worker at a call centre, which has been contracted to work on the tax credits scheme, talked to BBC 2's Working Lunch programme.

His identity has been protected.

Why don't callers get their questions answered?

"They are going on hold for anything up to an hour - and when they actually do get through on the helpline, chances are they get through to something that can only be explained as an overflow department.

"[The overflow department] cannot answer any of their queries whatsoever. They don't actually have the access to the information."

So people are ringing up and there isn't a chance they will get their questions answered?

"The only thing that we can actually say to the customer is the general state of play within the system.

THE TAX CREDIT FIASCO Guidance for those stuck in the Inland Revenue maze

"Until a couple of days ago we could arrange a call back, but we have now had that facility taken away from us as well."

But there is a chance they will eventually get through to someone at the Inland Revenue?

"The only chance of getting through to someone is to enquire about the details on your tax credit award notice.

"The chances of getting through to an Inland Revenue agent are very slim, because of the overflow of traffic going through the helpline.

"I speak to people who have been trying for days, if not weeks, trying to get through."

What sort of stories do you get?

"We've had circumstances where members of the public are irate and upset.

"The agents who are taking the calls are upset about the situation because they can't do anything.

"And it ends up there's a load of effing and blinding all over the place - and the calls have to be terminated."

What's your view about how the system is working?

"It is basically diabolical.

"As far as I can see the Inland Revenue has not actually thought about how many people are going to be applying for this.

"We are still dealing with people who sent in their claims in November last year and they are still awaiting payment.

"It should actually take six to seven weeks maximum to process the application."