PHILADELPHIA (Reuters) - Heavyweight boxing legend Muhammad Ali was honoured on Thursday for his humanitarian efforts and civil rights work at an awards ceremony in Philadelphia.

Boxing great Muhammad Ali waves after being awarded the Liberty Medal, as his wife Lonnie (L) and sister-in-law Marilyn Williams (R) look on, at the National Constitution Center in Philadelphia, Pennsylvania September 13, 2012. Ali, retired world heavyweight title holder, received the $100,000 award, sponsored by the nonprofit National Constitution Center, in recognition for his humanitarian efforts and work for civil rights at an awards ceremony on Thursday. REUTERS/Tim Shaffer

The $100,000 award called the Liberty Medal, sponsored by the non-profit National Constitution Center, was presented to Ali by his daughter, Laila Ali, a former boxer herself.

Ali, 70, who has been silenced by a long battle with Parkinson's disease, was honoured as an icon of constitutional ideals and the American dream, the center said.

He "has been an outspoken fighter for religious and civil rights; a conscientious objector who took his battle to the Supreme Court and won; an ambassador for peace and justice worldwide, and a tireless humanitarian and philanthropist," the center said in a statement.

"Muhammad Ali continues to this day to inspire young people throughout the world," Philadelphia Mayor Michael Nutter told the ceremony.

Since he retired from boxing in 1981, Ali has worked on philanthropic and social causes around the world. He has made goodwill missions to Afghanistan and North Korea, delivered medical aid to Cuba, travelled to Iraq to secure release of 15 U.S. hostages during the first Gulf War, and most recently, worked for the eventual release of the three American hikers held captive in Iran, the center said in its statement.

"We are here today to honour a true champion of freedom," David Eisner, the centre's president and chief executive, told the audience.

Ali did not speak at the ceremony, held in the hometown of his bitter former rival Joe Frazier, who died of liver cancer last November. But his wife, Lonnie Ali, said he was "deeply honoured ... to be a beacon of liberty."

(Writing by Barbara Goldberg; Editing by Tom Brown and Philip Barbara)

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