Gayle Killilea, the wife of bankrupt developer Seán Dunne, is seeking to block the National Asset Management Agency from forcing two US banks and a property agent to hand over personal financial information about her, claiming that the State loans agency is on “a massive fishing expedition”.

In a series of new court filings, Ms Killilea is seeking to intervene in Nama’s legal action against her husband and to quash subpoenas issued by the State loans agency against First Republic Bank, investment bank Credit Suisse and Coldwell Banker, a residential property agent.

She, along with her property company Mountbrook USA, is also seeking a protective court order claiming that Nama is attempting to use the lawsuit “to gather information to be used against Killilea in an action to be filed against her”, the bankruptcy court records state.

Nama is seeking Ms Killilea’s bank records “for private matters, such as the purchase of private items for herself of her children, for periods of time that have nothing to do with the matters raised in the complaint”, her attorney Eric Henzy says.

He argues Nama “should not be allowed to use this adversary proceeding to conduct this type of fishing expedition for the purposes of later pursuing claims against Killilea”.

Nama filed a lawsuit against Mr Dunne, who owes the agency €185 million, in his US bankruptcy proceedings in July, claiming that the Carlow developer omitted and misstated information in his court bankruptcy filings or at his meeting of creditors and that he removed, transferred and concealed assets.

The agency is seeking financial information on Ms Killilea and Mountbrook claiming Mr Dunne and his money are behind her multimillion dollar US property dealings.

Ms Killilea and Mountbrook held accounts at First Republic and she still has an account at Credit Suisse, while Coldwell Banker was retained for the lease on a property in Greenwich, Connecticut.