In October, Flutter reached an agreement to acquire Stars Group, to create a merged entity which would have generated £3.8bn ($4.66m) in revenue for 2018 on a pro forma basis.

At the time, the deal (worth £11bn in market capital) was expected to be closely scrutinised by regulators, given the new firm would hold a significant share in several markets, including the UK and US.

The CMA has now commenced phase one of its investigation into the deal for the UK market, which takes the form of an invitation to comment on the transaction "from any interested party;" the deadline for comment is 18 February.

Providing there is no regulatory obstruction, the merger between Flutter and Stars Group is expected to complete in Q2 2020.

It’s important to note this is no guarantee of intervention by the CMA and may end up prompting no further action.

A statement said: "The CMA is considering whether it is or may be the case that this transaction, if carried into effect, will result in a substantial lessening of competition within any market or markets in the UK for goods or services."