Known for his debonair style, raffish good looks and often mischievous joie de vivre, Sharif, who also gained worldwide fame as a bridge player, had Alzheimer's disease.
He died in Cairo of a heart attack, his agent Steve Kenis said in London.
"His psychological state had deteriorated, he wasn't eating or drinking," Hawwas told AFP.
Hollywood star Antonio Banderas called Sharif "a great storyteller, a loyal friend and a wise spirit".
"I will always miss him. He was one of the best," he tweeted.
Italian actress Claudia Cardinale, who acted with Sharif in Jacques Baratier's 1958 film Goha, expressed her "great sadness".
Renowned Egyptian actress Youssra told AFP: "I feel awful, I just lost (one) of the best people in my life, I feel so lost and unhappy and helpless".
The actor's grandson Omar Sharif Jr tweeted: "I join my family in thanking everyone for the global outpouring of prayers & support we've been receiving. I will miss my grandfather dearly."
- Propelled to stardom
Sharif began acting in the 1950s and his most high-profile roles were in the 1960s when he won an Oscar nomination for "Lawrence of Arabia" and Golden Globes for the same film and for "Doctor Zhivago".
His role in "Lawrence of Arabia" as Sharif Ali, an Arab chief enlisted by Peter O'Toole's T.E. Lawrence in Britain's fight against the Turks in World War I, propelled him to stardom, setting the stage for an even higher profile role in David Lean's subsequent release, "Doctor Zhivago".
Sharif played the hero in the epic adaptation of Boris Pasternak's novel of tortured passions during the Russian Revolution, with his real-life son Tarek
The actor, fluent in Arabic, English, French, Greek, Italian and Spanish, went on to star in many films and television productions, including alongside Barbra Streisand in 1968's "Funny Girl".
But he never again scaled the heights of critical
Sharif kept working over the following decades, often in
"I'd rather be playing bridge than making a bad movie," he once said, before announcing in 2006 that he had given up the game.
2003 comeback
Sharif made something of a comeback in 2003 in the title role of the French film "Monsieur Ibrahim", playing 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.
Born Michel Demitri Shalhoub on April 10, 1932 in the Mediterranean city of Alexandria -- at the time a cosmopolitan hub -- to parents of Syrian and Lebanese extraction, he was raised a Catholic.
He studied at Alexandria's Victoria College before gaining a degree in mathematics and physics from Cairo University.
He joined his father's lumber business, but the acting bug had taken hold while he was studying, and in 1954 he made his silver screen debut in the Egyptian film "Siraa Fil-Wadi" ("The Blazing Sun") by Youssef Chahine.
The movie's romantic intrigue was echoed off screen as he married the leading lady, famed Egyptian actress Faten Hamama, converting to Islam and renaming himself Omar Sharif.
They had one son, Tarek, before divorcing in 1974 when Sharif launched his Hollywood career.
Playboy lifestyle
Sharif never remarried, but had another son, Robin, from a brief relationship with Italian journalist Lula De Luca.
He lived between France, Italy and the United States, before settling again in Egypt.
His playboy lifestyle of fine hotels, casinos and restaurants from California to the Cote d'Azur was not without its brushes with controversy.
In August 2003, he received a one-month sentence and a fine for
He was also ordered to take an anger management course by a California court in 2005, after punching a parking attendant.
Sharif had a triple heart bypass in 1992 and suffered a mild heart attack in 1994, according to the IMDb movie database website. The 100-cigarettes-a-day smoker quit after the operation.
In January 2011, during Egypt's popular uprising Sharif called for then president Hosni Mubarak to stand down, while at the same time expressing doubts about the Muslim Brotherhood.