Social worker and councillor Jonathan Bell was nominated by the DUP following Mrs Robinson's resignation earlier this month from her Strangford seat at Stormont and Westminster.

Mr Bell is senior practitioner in the adolescent social work team based in James Street, Newtownards. He has eight years' experience in local government and is a former District Policing Partnership (DPP) chairman.

Mrs Robinson is under police investigation after securing £50,000 from two wealthy property developers to fund her toyboy lover's restaurant business.

Police in Belfast said their organised crime branch, which specialises in complex financial probes, had been called in to establish whether any criminal offence had been committed.

Mrs Robinson, 60, was given £25,000 by each of the two developers, Kenny Campbell and Fred Fraser, to help Kirk McCambley, 21, establish his business, the Lock Keeper's Inn on the banks of the River Lagan in south Belfast. She kept £5,000 for herself.

In the immediate aftermath of the sex and money scandal, mother-of-three Mrs Robinson, wife of First Minister Peter Robinson, announced she was resigning as MP for Strangford as well as her membership of the Stormont Assembly.

She has also been dumped by the DUP, of which her husband is leader.

She is currently undergoing acute psychiatric treatment after trying to kill herself last March when she confessed to her husband about her secret affair.