Costs do not have to prevent a full review of lobbying by ex-DUP politician Iris Robinson on planning cases.

That’s the message to DUP Environment Minister Edwin Poots today from a businessman who is ready to underwrite the expense of any research.

The minister last week gave details of three cases since 2003 where Mrs Robinson made representations on applications by developers Fred Fraser and Ken Campbell.

It was recently revealed that she solicited £50,000 from the two men in 2008 to bankroll the cafe business of her teenage lover Kirk McCambley.

Mr Poots said his Department was unable to provide a definitive list of cases where Mrs Robinson had lobbied for the pair, as a full manual trawl of planning files would involve “disproportionate” costs.

That has now prompted an intervention by prominent developer Peter Curistan, the man behind Belfast’s flagship Odyssey centre.

He told the Belfast Telegraph: “I was surprised at Mr Poots ruling out a full review on grounds of expense. To promote the cause of transparency in planning, I am prepared to underwrite the costs.

“I am also ready to pay for independent researchers to come in and conduct the research, if the Planning Service is prepared to facilitate that.”

Responding, a DoE spokesman said: “In the interests of transparency and accountability, Planning Service has an open file policy in operation and any member of the public, journalist and public representative is entitled to view any planning file. Planning Service will facilitate all requests for viewing by appointment.”

The open file policy normally involves access to applications on a case by case basis, rather than the full planning history of particular applicants.

Mr Poots gave details of the three planning application representations by Mrs Robinson in reply to Assembly questions from Sinn Fein MLA Daithi McKay.

They involved housing development proposals at sites in Newtownards and Comber.

In one of the cases, approval was granted despite objections from within the local community.