AIB has announced plans to finance 'green' commercial buildings.
The bank previously set a target of making €5 billion worth of green loans available over the next five years.
The finance was open to homeowners who want to make their home more energy-efficient or drivers who want to buy an electric car.
However, AIB CEO Colin Hunt says they are now extending the green fund to businesses.
The framework will support lending to projects in energy-efficient buildings, renewable energy, C)2 reduction and other climate-related initiatives.
Mr Hunt says that AIB believe that banks have a key role to play in creating a sustainable future.
AIB has become a Founding Signatory of the UNEP FI (United Nations Environment Programme – Finance Initiative) Principles for Responsible Banking, which is committed to strategically aligning businesses with the Sustainable Development Goals and the Paris Agreement on Climate Change.
AIB joins a coalition of 130 banks worldwide, representing over €42.7 trillion in assets, in committing to taking on a crucial role in helping to achieve a sustainable future.
"We look forward to further aligning our activities to the UN Sustainable Development Goals and the Paris Agreement," said Mr Hunt.
"Our launch of a Green Bond Framework is a further step on this journey.
"Through this framework, we are backing our customers in addressing the transition to a low-carbon economy and are showing our intent to our investors to lead the way in funding sustainable Irish business.”