New York investor Martin T. Sosnoff on Monday sweetened his unsolicited takeover bid for Caesars World Inc. by 14% to $32 a share, or $931.2 million.
At the same time, Sosnoff said in a letter to Caesars Chairman Henry Gluck that shareholders "will be best served by our entering immediately into good-faith, friendly negotiations."
Gluck had declined earlier negotiation offers, most recently last Wednesday, Sosnoff said.
Caesars' stock closed up 25 cents to $32.375 on the New York Stock Exchange.
Caesars spokesman Jack Leone said the company was studying Sosnoff's latest offer and had no further comment.
Caesars operates hotel-casinos in Las Vegas and Lake Tahoe, Nev., and Atlantic City, N.J., as well as Poconos resorts in Pennsylvania.
Five weeks ago, Sosnoff made his initial cash offer of $28 per share for all Caesars stock he doesn't already own. Sosnoff currently owns 12% of the company's stock on a fully diluted basis.