The UK owner of the Ladbrokes, Coral and Sportingbet brands is in advanced talks about a joint venture with US hotel and casino operator MGM Resorts.
GVC Holdings had been considering opportunities in the US after the Supreme Court paved the way to legalise sport betting.
GVC confirmed in a statement that discussions were “at an advanced stage regarding such a joint venture”.
MGM is best known for Las Vegas brands such as the MGM Grand and Bellagio.
Sky News, which first reported details of the proposed deal, said the two companies would initially invest about $100m (£76m) each in a venture focussed on sports betting. But the alliance could pave the way for a full merger.
UK betting firms have been looking closely at the US market after the US Supreme Court in May overturned 1992 legislation that banned sports betting in most states.
In May, gambling firm Paddy Power Betfair bought the US fantasy sports betting site Fan Duel.
Fan Duel lets its customers bet on fantasy sport games, based around NFL American Football, NBA basketball, MLB baseball and NHL ice hockey.
GVC has grown rapidly through acquisitions, including the purchase of Ladbrokes last year.