Senior officials in the Department of Social Protection flagged significant staffing concerns months before it was officially confirmed that there were serious delays in the payment of Maternity Benefit.

Speaking last month on RTÉ’s Morning Ireland, then minister for social protection Leo Varadkar apologised for delays in maternity benefit payments, which resulted in new mothers waiting for up to four weeks for payment.

However, documents released under the Freedom of Information Act show that staffing levels in the department had become unsustainable months earlier and warnings were issued that payments would be delayed unless new staff were hired "immediately".

Mr Varadkar said last month he could not say for certain what the reason for the delays were, and that they had been happening for a few weeks.

However, on 14 February a principal officer with responsibility for maternity benefit, Tony Kiernan, wrote an email to Helen Faughnan, an assistant secretary in the department, warning about staffing levels.

"Unless we get an extra staff injection (and I am saying we need six immediately) we will remain in a position where we are paying far too many maternity benefit claims after the commencement of leave date," he cautioned.

"We are working hard to get back on track but the figures just don’t add up."

The correspondence indicates that senior officials were aware there was a problem with Maternity Benefit, and confirms that the delays were already happening, three months before the minister apologised.

Another document in March shows that the office in Buncrana, Co Donegal was down seven staff, or one fifth of the total workforce. The staffing crisis continued through April with Mr Kiernan writing "we are losing staff as quickly as we get them".

While the delays were ongoing, 600 calls a day were being dropped at the Buncrana call centre.

The documentation also raises questions about the impact that the introduction of Paternity Benefit in September last year had on the department’s capacity. Both payments are dealt with by staff at the Buncrana centre.

Mr Varadkar said he did not think the paternity scheme had resulted in increased pressure on the department’s ability to process Maternity Benefit. "That is certainly not what I have been told by my operations people," he told Morning Ireland.

However, correspondence released to RTÉ suggests department staff were aware of serious issues with the new payments. In a briefing document the department explained the same staff were processing both payments.

"This resulted in a proportion of the 24 experienced staff having to be allocated to both schemes, diminishing the experience level in the maternity section," Mr Kiernan wrote.

"Consequently processing maternity claims was slower than normal in September, October, and November. The impact of this became evident in 2017."

Mr Kiernan wrote that a new IT system had to be implemented a month earlier than anticipated "to accommodate the earlier start date for Paternity Benefit".

Additional correspondence also indicates that Mr Varadkar’s press adviser, Nick Miller, suggested removing Paternity Benefit from a written statement provided by the department in response to media questions.

In a draft to queries from Morning Ireland the department said the delays were caused, in part, by "refining the Paternity Benefit system".

Following email correspondence from Mr Miller, reference to Paternity Benefit was removed from the department statement.

The documents also show that following the story’s publication there was a flurry of emails exchanged putting contingencies in place and redirecting staff.

Processing time for maternity claims is now back to normal.