A £1 billion deal for Nama's Northern Ireland loan book would be rendered illegal if any third party "fixers" were wrongly involved, the High Court heard on Monday.
Counsel for Belfast businessman Gareth Graham told a judge investigations into the sale to US investment fund Cerberus are under way in three different jurisdictions.
Referring to claims a £7 million fee was to be paid out as part of the transaction, Monye Anyadike-Danes QC said: “If it turns out that these agencies uncover illegal transactions then that taints that sale.”
She also raised concerns about alleged meetings between Cerberus and administrators in a disputed process to sell one of the repossessed Graham properties.
Mr Graham is a director and shareholder in property companies that own a variety of commercial and residential premises in Belfast. The firms’ loans were among those transferred to Nama.
Last year Cerberus bought Nama’s entire Northern Ireland portfolio in a deal worth more than £1 billion.
Mr Graham is locked in a legal battle over the validity of the appointment of administrators to his companies.
Contending that his businesses were financially strong, his legal team are set to claim an improper motive was involved.
With the main case not due to be heard until January, administrators acting for Cerberus are now seeking to sell the Lyndon Court building in Belfast. Their lawyers argued judicial directions issued previously only require that notification is given to the court.
But Mr Graham is opposed to the deal going through without his consent or court order.
Ms Anyadike-Danes insisted the administrators had signed up to a restraint on any sale until after the trial.
She told the court: "The context we are dealing with here is a possible illegality . . . concerning the sale of the Northern Ireland loan book to Cerberus." Pressed by Mr Justice Horner for details, she mentioned the potential involvement of third parties in the deal.
The court was also told investigations into the loan portfolio deal are now being carried out in Northern Ireland, the Republic and the United States. The case continues.