Stormont's finance committee has criticised Nama's refusal to give evidence on its Northern Ireland loan book sale.

The watchdog said the controversy could be seen as damaging to the reputation of administrations on both sides of the Irish border.

It identified shortcomings in how the Irish Government and Nama handled the bidding process for its massive property portfolio.

The committee said it found the refusal of Nama to attend an oral evidence session particularly unhelpful.

"Nama needed to be more open and accessible given the importance of the Project Eagle portfolio to the Northern Ireland economy," it was stated.

"The committee does not accept Nama's rationale for not attending an oral hearing of the committee, especially given that agency representatives have previously held many meetings with ministers and officials in Northern Ireland."

All parties involved in the £1.2bn transaction in 2014 have denied wrongdoing.

The sale is also being investigated by the UK's National Crime Agency (NCA).

The finance committee report said: "From the evidence to date, the committee is concerned that different aspects of the Project Eagle controversy could be seen as having caused reputational damage to DFP (Department of Finance and Personnel), the Northern Ireland Executive, the Irish Government and Nama respectively.

"In the case of DFP and the Executive, this relates to how the nominations were made for appointments to the Nama Northern Ireland Advisory Committee and from the perceptions arising from involvement of ministers with potential purchasers of Nama-secured assets in Northern Ireland.

"In the case of the Irish Government and Nama, the available information suggests shortcomings in the handling of the bidding process and related decisions.

"It is therefore imperative that the lessons identified to date are acted on as applicable."