Update - 5.30pm: The government should buy some of the non-performing mortgages being sold by banks, according to a People Before Profit TD.
Ulster Bank confirmed earlier it plans to sell around 7,000 mortgages - that's on top of the 18,000 to be sold by Permanent TSB.
The news has lead to fears unregulated vulture funds may buy the majority of the distressed mortgages.
TD Richard Boyd Barrett said the government needs to step in and help people "saddled with massive debt who do not know how to cope".
He went on: "The banks have not been the most pleasant people to deal with so it is not surprising many people are burying their heads in the sand."
His comments follow calls by Sinn Fein and Fianna Fail for new laws to regulate vulture funds.
Sinn Fein's finance spokesman Pearse Doherty said the mooted sale will "end in tears" and will result in an increase of home repossessions.
Deputy Doherty told RTE's Morning Ireland programme warned that repayment options offered by banks will not be provided by vulture funds and said families in arrears should also be offered the type of write-downs being offered by vulture funds.
Deputy Doherty warned that no court could force vulture funds to offer options to distressed mortgage holders and suggsted Ulster Bank chief executive Gerry Mallon's failure to appear with his colleagues before the Oireachtas Finance Committee was a "snub to the committee and to the Irish people".
Fianna Fail finance spokesman Michael McGrath said swift action is needed to ensure that such international investors are fully monitored by the Central Bank ahead of any loan portfolio sale.
Finance Minister Paschal Donohoe has previously said the Government cannot prevent the sales but that he is deeply aware of homeowners' concerns. Laws on repossessions are being reviewed as a result.
But Mr McGrath said: "The case for full regulation of these vulture funds is compelling.
"If the fund buys a mortgage, a farm loan or an SME loan, it makes all the crucial decisions about the future of that loan. Despite this, the vulture fund is untouchable, unaccountable and entirely beyond the reach of the Central Bank."
Fianna Fail is to introduce new legislation on regulation next week.
Mr McGrath also called for the 2013 Code of Conduct on Mortgage Arrears to be reviewed. He said 38,000 family home mortgages now owned by non-bank entities, including over 11,000 by unregulated vulture funds.
"Mortgage holders who are fully honouring the terms of a restructuring agreement need greater protection," the opposition spokesman said.
"The fact that vulture funds do not have to offer some of the main restructuring options such as arrears capitalisation, term extension or split mortgage places distressed borrowers whose loans are with them in a perilous position."
Update - 11.30am: Ulster Bank's CEO Gerry Mallon has said the bank will try to sell their loan book as long as it is legal.
He said: "We operate under a framework of laws and regulations and neither of these are optional to us, so the laws are a matter for the lawmakers and the regulations are a matter for the regulators.
"We'll do whatever is required to comply with both, we'll have a portfolio that we will bring forward to the market and we'll see who is eligible and interested to buy it."
9.41am: Ulster Bank to sell up to 7,000 home loans; Warning mortgage sales will lead to surge in repossessions
Ulster Bank has today admitted that it intends to sell up to around 7,000 home loans.
The bank has published its full-year results this morning which show it had an operating loss of €151m in 2017.
The sale would make it the second major bank in the country to try to put non-performing mortgages on the market.
Permanent TSB still has not found a buyer for the 18,000 home loans it has been trying to sell.
Ulster Bank's CEO Gerry Mallon said that his bank now intends to make a similar move.
"Part of our strategy and one of the things we've made an adjustment in our accounts for is the fact that we reckon that a loan sale is one of the things we'll have to deploy and it could be approximately a third of the overall non-performing loan book," he said.
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