The Central Bank has laid out new, tougher targets for lenders dealing with homeowners at risk of defaulting on their mortgages.

Banks will be required to have concluded deals with customers representing 25% of mortgage loans where borrowers are behind on repayments for more than 90 days by the end of next year.

Lenders have already been set targets by the Central Bank which stipulate that they must have offerred ''sustainable solutions'' in respect of 30% of their 90-plus day arrears loan books by the end of this month and 50% by the end of the year.

As previously revealed by RTÉ, the IMF/EU Commission/ECB Troika has been pushing for concrete targets on the number of deals which must be concluded with distressed borrowers as distinct from simply having made "offers" of sustainable solutions.

Bank executives from AIB, Bank of Ireland and Permanent TSB were criticised at recent Oireachtas Finance Committee hearings after admitting that legal letters demanding repayment from defaulting borrowers were, in many cases, considered by the banks to be "sustainable solutions" for the purpose of meeting the Central Bank targets.

The most immediate deadline now facing the banks, though, is to have concluded agreements with at least 15% of their most serious arrears cases by the end of this year.

In a statement on the new targets, the Central Bank said it was "now setting expectations for end March 2014 for sustainable solutions offered to customers to reach 70% of over 90-day arrears and for concluded solutions to reach 25%".