The Public Prosecution Service (PPS) has said that former DUP MP Iris Robinson will not face charges over her role in helping her 19-year-old lover set up a business.

Mrs Robinson, a devout Christian who has called homosexuality “abhorrent”, was questioned by police last year over her role in Kirk McCambley’s business affairs.

She had admitted to having an affair with him, while he was aged 19 and she was aged 59.

The BBC’s Spotlight programme reported that she had asked two property developers for £50,000 to help him set up a cafe.

She did not declare this to Stormont, Westminster or Castlereagh council, which granted Mr McCambley a lease. Mrs Robinson was a councillor for Castlereagh at the time.

After news of the affair broke, she resigned from politics, quitting her seat in Strangford and her place on the Northern Ireland Assembly, and was thought to be receiving psychiatric care.

On Friday, the PPS said: “Following careful consideration of all the available evidence, a decision has been taken not to prosecute in this case.”

A statement from the Robinson family to the BBC said: “We note the decision of the Public Prosecution Service.

“In the year since the Spotlight programme with the police investigation and council investigation ongoing we have amassed substantial material demonstrating serious and damaging inaccuracies in the BBC Spotlight programme.

“Mrs Robinson will be making, through her solicitor, a detailed statement following the publication of the report commissioned by the council and all legal options are now under active consideration.”

The BBC said it stood by its report.

Mrs Robinson tried to kill herself after admitting the affair to her husband Peter Robinson, Northern Ireland’s first minister.

He has denied any knowledge of her financial affairs.

Deeply religious Mrs Robinson was seen as a hypocrite for her affair with Mr McCambley, who was young enough to be her grandson, because of her homophobic views.

In the past four years, she has called homosexuality an “abomination”, compared to it to paedophilia and suggested gays and lesbians can be “cured”.