"The board confirms that it has received an indicative offer from Hilton Hotels Corp., which it is currently evaluating," Hilton Group officials say in a statement.

"While discussions are ongoing, a definitive agreement has not been signed and there can be no assurance that any transaction will result from such discussions," spokespeople for Hilton Hotels Corp. say in a separate, brief statement. Shares in Britain's Hilton Group jumped 19% immediately after the announcement this morning.

"This is a great deal if it comes about because it means US hotel operators are looking to come to Europe to diversify their income streams," says one analyst. Industry watchers had valued the London-based Hilton's 400-plus hotels at around euro 4.66 billion ($5.66 billion), but sources say a bid price of euro 5.25 billion ($6.03 billion) is more in order. Because of the close links between the two groups analysts say a counter bid is very unlikely, but they expect other US groups like Marriott International to begin to look to Europe.

Hilton Hotels owns, manages and franchises more than 2,300 hotels, while the two Hilton companies operate a joint venture to expand the luxury Conrad brand, named after the company's founder, which has about 20 hotels.

Ladbrokes acquired the Hilton business outside the US in 1987 and changed its name to Hilton in 1999 after it acquired the Scottish casino and hotel operator Stakis. With the hotels sold Ladbrokes would be worth around £3.7 billion and remain in the FTSE-100 Index, analysts conclude.