Shares in Ladbrokes and Coral owner Entain fell sharply on Tuesday afternoon after it was revealed that US casino giant MGM Resorts International does not intend to make a firm bid for the company.
Entain had this month rejected an £8.1 billion takeover proposal from its partner in the US joint venture, BetMGM, saying it "significantly" undervalued the company.
MGM had until February 1 to make a firm offer for Entain but has decided to scrap its plans "after careful consideration and having reflected on the limited recent engagement between the respective companies".
The announcement led to Entain's share price falling by nearly 12 per cent to 1,245p by close of trading on Tuesday.
MGM's chief executive Bill Hornbuckle added: "BetMGM, our US sports betting and online gaming venture with Entain, remains a key priority for the company as we continue to leverage our pre-eminent physical gaming, entertainment, and hospitality platform to expand digitally.
"We believe BetMGM has established itself as a top three leader in its markets and we remain committed to working with Entain to ensure its strong momentum continues as it expects to be operational in 20 states by the end of 2021."
MGM added it reserved the right to set aside its statement in the event of a change in circumstances such as the agreement of the Entain board or if a third party announced a firm intention to make an offer for Entain.
Responding to the news, Entain said it had a "clear growth and sustainability strategy, backed by leading technology, that it is confident will deliver significant value for stakeholders".
It added: "We look forward to continuing to work closely with MGMRI to drive further success in the US through the BetMGM joint venture."
It has been a turbulent month for Entain, whose chief executive Shay Segev announced his intention to step down last week after less than six months in the role.
According to a report last week by Sky News, non-executive director Jette Nygaard-Andersen is in advanced talks to take over at the helm of the company, until recently known as GVC Holdings.