Egyptian-born film legend Omar Sharif, star of such classics as Lawrence of Arabia (1962) and Doctor Zhivago (1965), is suffering from Alzheimer's disease, his agent said.
The agent, Steve Kenis, confirmed news first reported by the Spanish daily El Mundo, which cited the 83-year-old actor's son Tarek. Kenis gave no further details in an email.
Known for his charismatic good looks and bridge-playing prowess, Sharif is resting at his home in Egypt, according to the Los Angeles Times newspaper.
Born in 1932 the son of a lumber merchant in Egypt's second city Alexandria, Sharif was nominated for an Academy Award in 1963 for his role as Sherif Ali in Lawrence of Arabia.
Sharif, who was raised a Roman Catholic, started acting in the 1950s and had his most high-profile roles in the 1960s, when he also starred in Funny Girl opposite Barbra Streisand in 1968.
He kept working over the following decades, often in TV movies, and made something of a comeback in 2003 in the title role of the French film Monsieur Ibrahim (2003) in which he played an elderly Muslim shopkeeper.
The performance won him a best actor award at the Venice Film Festival and the best actor Cesar, France's equivalent of an Oscar.
In January this year, Sharif's actress ex-wife Faten Hamama died aged 83 after a career spanning seven decades and almost 100 films alongside masters of Egypt's film industry. She was buried at her family cemetery in Cairo.