LOS ANGELES, Calif. - Hotel magnate Barron Hilton will give US$2.3 billion, the bulk of his fortune, to charity, officials said Wednesday.

Hilton, the 80-year-old grandfather of Paris Hilton, bequeathed the money to the Conrad N. Hilton Foundation, a charity founded by his father in 1944.

"We are all exceedingly proud and grateful for this extraordinary commitment," Hilton's son Steven M. Hilton, president and chief executive of the foundation, said in a statement.

"Working to alleviate human suffering around the globe, regardless of race, religion or geography, is the mandate of the foundation set by my grandfather ... and now reinforced by my father."

The funds will partly come from the sale of the Hilton Hotels Corp. to The Blackstone Group.

The money will go into a trust but eventually will find its way to the foundation. Hilton, the chairman of the foundation, pledged an immediate US$1.2-billion donation to the charity, with an estimated US$1.1 billion to follow after his death.

Hilton had indicated at a recent board meeting that he would follow in his father's footstep by leaving nearly all of his fortune to the trust when he died in 1979.

The charity has distributed more than US$560 million for programs that house mentally ill homeless people, prevent substance abuse and increase access to safe water in Africa and Mexico. A significant portion of the money helps the work of Catholic Sisters.