The owner of Paddy Power is merging with a Canadian rival, to create the largest online betting and gaming operator in the world.
The boards of Flutter Entertainment and The Stars Group (TSG) have reached agreement on the terms of a recommended all-share deal.
TSG is to be bought by Dublin-based Flutter, which owns Paddy Power.
The deal will bring the two businesses together with combined annual revenue of stg£3.8bn (€4.26bn) - making it the largest online betting and gaming operator globally.
The group will be incorporated, headquartered and domiciled in Dublin - with a premium listing on the London Stock Exchange and a secondary listing on Euronext Dublin.
Its product offering will be across sports betting, poker, casino, fantasy sports and free-to-play games.
The two companies say the combination will "accelerate delivery" of Flutter's growth strategy.
This includes a plan to maximise profitable growth in its core markets of Ireland, the UK and Australia.
It will also provide capabilities to accelerate growth across international markets, and attain new podium positions in Spain, Italy and Germany.
Upon completion, it is intended that the group's board will be made up of 14 people.
Gary McGann, currently chairman of Flutter, will assume the role of chairman of the combined group.
Peter Jackson, currently CEO of Flutter, will assume the role of CEO of the group and Rafi Ashkenazi, currently CEO of TSG, will become group COO.
Commenting the announcement, Mr McGann said: "This is an exciting and transformational combination that will bring together two strong, complementary businesses to create a global leader in the fast-growing online sports betting and gaming industry.
"Under Peter Jackson's leadership we will bring together a management team with the experience required to ensure a successful integration of the businesses, with minimal disruption, during a time of unprecedented change in the sector.
"The combined group will be a strong voice in the promotion of responsible gaming worldwide and will lead industry standards on the protection of customers, whilst building sustainable relationships with them."
Approval of shareholders is expected to be sought in the second quarter of 2020.
While the transaction is expected to be completed during the second or third quarter of next year.