Minister for Finance Michael Noonan has defended the Government's handling of the sale of 13,000 mortgages, which were issued by Irish Nationwide.
Mr Noonan said there would be no change in the contractual position for individuals who hold the mortgages, regardless of who purchases it.
However, the homeowners are concerned they could lose basic protections under the Code of Conduct on Mortgage Arrears, which are separate to the legal terms of a loan.
The code only applies to companies that are regulated by the Central Bank.
But mortgage holders fear their loans could be bought by an unregulated, so-called 'vulture fund'.
The mortgages are being sold by the liquidators of IBRC, which is made up of the former Irish Nationwide and Anglo Irish Bank.
The issue was highlighted in a report on RTÉ's Prime Time on Monday night.
Mr Noonan said the Irish Nationwide mortgage book was not the first mortgage book that had been sold.
He said two tranches of mortgages had been sold already.
In both cases, he said, the purchasers were outside the regulatory system and voluntarily agreed to apply all the Central Bank protocols for dealing with customers in mortgage arrears.
He said in the small number of cases that go to court for repossession, a lender would be asked if they had fulfilled all the obligations under the Central Bank protocols, and the court would not issue an order unless they had.
He said he would wait and see who buys it and then he will advise them that there are protocols in Ireland and that they are expected to fulfil them.
He said it was his objective that when the mortgage books are sold, the mortgage holders would have the same level of protection that they do at present.
Meanwhile, Fianna Fáil has published proposed legislation aimed at protecting mortgage holders whose loans are sold to unregulated third parties.
The Protection of Residential Mortgage Account Holders Bill 2014 was published today.