Hilton Hotels Corporation has agreed to be acquired by The Blackstone Group.

InterContinental Hotels has been lifted by the US private equity firm's takeover deal for Hilton Hotels Corp for about $20 billion plus debt, the richest in a series of recent private equity offers for hotel companies.

The deal would instantly make Blackstone the world's largest hotel owner. Hilton has more than 2,800 hotels with 480,000 rooms 76 countries and territories.

InterContinental Hotels has had the number one ranking for the past four years.

The private equity group said it would combine cash from its real estate and corporate private equity funds to buy all outstanding Hilton shares for 47.50 US dollars each, a 32% premium over Tuesday's closing stock price.

Hilton's board approved the terms on Tuesday. The company said the deal would close in the fourth quarter pending shareholder approval.

Blackstone owns more than 100,000 hotel rooms in the United States and Europe, including La Quinta Inns and Suites as well as LXR Luxury Resorts and Hotels.

Hilton has been aggressively expanding since 2005, when it bought Britain's Hilton Group PLC for $US5.7 billion, reuniting two brands that split in the 1960s.

Socialite Paris Hilton's grandfather, Barron Hilton, is co-chairman of the board and owns 5.3% of Hilton Hotels' outstanding shares, according to the company's latest proxy statement.

Hilton shares rose 2.18 US dollars, or 6.4%, to 36.05 US dollars on Tuesday in trading shortened ahead of the July Fourth holiday. InterContinental was amongst top FTSE gainers, up 3.9%.