A former Sinn Fein press officer who has admitted child sex offences was employed directly by Michelle O’Neill during his time working at the Northern Ireland Assembly.

The Assembly has confirmed that Michael McMonagle was employed by Ms O’Neill and three other Sinn Fein MLAs across two periods, when his salary was paid for by Assembly allowances provided from the public purse.

McMonagle was paid out of Ms O’Neill’s staffing allowance between March and May 2020, at a time when she was Stormont deputy First Minister.

Parties can hire staff from Assembly funds provided to them centrally, or individual MLAs can hire them from their own staffing allowances.

The latest development in the controversy came before Ms O’Neill faced Assembly questions on the McMonagle furore.

Stormont Speaker Edwin Poots has selected an urgent oral question for Ms O’Neill on the matter in the Assembly on Monday.

Last month, McMonagle, 42, from Limewood Street, Londonderry, admitted a series of offences, including attempting to incite a child to engage in sexual activity.

He was first arrested in August 2021.

Sinn Fein has said it suspended him as soon as it became aware of the police investigation. His term of employment with Sinn Fein at the Assembly formally ended in July 2022.

McMonagle then went on to get a job with the British Heart Foundation (BHF), which did not know he was under investigation for child sex offences.

Sinn Fein has been under mounting pressure after it emerged that two former party press officers provided references for McMonagle in 2022 for the BHF job.

The press officers quit more than a week ago after Sinn Fein began disciplinary proceedings against them.

In a further development at the weekend, Sinn Fein acknowledged that the BHF had contacted an HR official in Sinn Fein in August 2023 to query the references, after media coverage of McMonagle being charged.

Ms O’Neill has said she was not made aware of that contact at the time.

On Monday, in response to a media query from the PA news agency on how McMonagle was paid, an Assembly spokesman said: “Michael McMonagle was employed jointly by former MLAs Daithi McKay and Mitchel McLaughlin in a full-time position from 6 May 2014 to 31 October 2014.”

The spokesman added: “Michael McMonagle was employed by Michelle O’Neill MLA from 2 March 2020 to 31 May 2020 and then by Jemma Dolan MLA from 1 June 2020 to 8 July 2022 in a full-time position.”

Earlier, Fearghal McKinney, head of the BHF in Northern Ireland, said the charity had suffered reputational damage over the matter.

He said the charity was dismayed when their due diligence appeared to have been questioned last week by senior Sinn Fein figures, including Ms O’Neill.

Mr McKinney spoke to Ms O’Neill on Saturday and said she expressed regret over comments she made last week, that there were lessons for a lot of people in terms of “due diligence for an employer when they take on an employee”.

“This caused enormous distress and anxiety among our staff and unwavering supporters,” he told the BBC.

“It was quite clear that whenever comments were made about due diligence that there was only one other organisation that employed him since he was employed by Sinn Fein, so clearly there was a reflection on us.”

He said any damage to the charity could undermine their good work.

“When this happened and there was damage caused, as we saw it, to our reputation, added damage we thought around the public comments that were made, we had to do something to make sure that the record was put straight,” he said.

“We’re content that we have done everything in our power in order of keeping all our supporters, all our staff and the wider public that’s connected with us safe, and they know that that’s the standard that the British Heart Foundation applies.”