Facebook has said it is expanding its investment in Ireland by acquiring a long-term lease of 14 acres for a new campus development in Ballsbridge in Dublin.
The premises, known as the Bank Centre, is currently occupied by AIB.
The move will substantially increase its floorspace in the city, enabling it to expand its workforce by up to 5,000.
Facebook has been in Ireland for nearly ten years and currently employs 4,000 people across a number of city centre locations.
This deal, which was widely expected, will see it acquire the 14-acre site in the south Dublin suburb, allowing it to grow its floor space to 870,000 square feet.
The new campus will play host to the 60 teams it has in Ireland across engineering, safety, legal, policy, marketing and sales.
They work on a wide range of products including Facebook, Instagram, WhatsApp and Oculus.
It currently has its International Headquarters in Grand Canal Square, as well as a facility at Samuel Beckett Building in Dublin 3, a data centre in Clonee in Co Meath and Facebook Reality Labs in Cork.
"This significant investment in a 14-acre campus with capacity for thousands more employees demonstrates our commitment to Ireland, our desire to grow our business here and continue to contribute to the economy," said Gareth Lambe, Head of Facebook in Ireland.
He added that the site will be renovated in phases, and as a result the move to it will happen over three years.
All 2,000 employees currently based in Grand Canal Square will have moved to the new campus by 2022.
The investment has been welcomed by the Minister for Business, Heather Humphreys, who said it is a landmark day for Facebook, adding it is a huge vote of confidence in the country.
Chief executive of IDA Ireland Martin Shanahan said today's announcement further deepens Facebook's commitment to Ireland.
He said that it had become the primary strategic international hub for the company; servicing millions of users across Europe, the Middle East and Africa and the development of its campus in Ireland will provide the company with the potential to expand its operations.
An AIB spokesman said the bank had signed a series of agreements to complete the gradual exit of Bank Centre by the end of 2020.
The spokesman said the bank's corporate headquarters building in Molesworth Street is progressing as planned, with expected occupancy in the first half of 2019.
Earlier this year, AIB opened its Central Park office in Sandyford where staff work on products and services for its retail and SME customers.
The bank also said it is close to confirming a third property announcement, which is believed to be in the Heuston South Quarter area in Dublin city.