AIB has joined the growing number of banks that allow customers moving house to retain their tracker mortgages.

In a letter to Fianna Fáil's finance spokesman Michael McGrath, AIB Chief Executive David Duffy said customers would pay the existing tracker rate, plus a further 1% for the duration of the mortgage if they move home.

The development will take effect from the summer. It will be available to customers of EBS and AIB.

If a customer is moving home and wants to borrow further money, they would have to do so at the higher interest rate that applies to new business.

The new tracker arrangement will be available for customers trading up or down from their current residential property.