Egyptian President Hosni Mubarak temporarily handed over power to the prime minister as he underwent a gall bladder operation on Saturday in Germany, the state—owned news agency reported.

The 81-year-old leader, who has governed for nearly three decades, was diagnosed with “severe inflammation of his gall bladder” after tests at a hospital in Heidelberg, according to MENA.

The news agency said the operation was a success. Mr. Mubarak was conscious, and spoke with family members in the intensive care unit, the agency reported.

Mr. Mubarak, who was accompanied by his wife and two sons, has decreed that Prime Minister Ahmed Nazif, will exercise all presidential powers while he is out of the country, MENA said.

Mr. Mubarak’s term in office ends next year and concern about his health often prompts speculation about the leadership of the Arab world’s most populous nation, a U.S. ally that plays a critical role in issues ranging from Mideast peace efforts to curbing Islamic militancy.

In a show of support, parliament speaker Fathi Serour, said millions of Egyptians will praying for Mr. Mubarak to return home “safe and sound.”

In recent months Mr. Mubarak has looked weakened and pale in several appearances. During a July visit to Italy he was photographed being helped up the stairs. Many diplomats and Egyptian political observers believe the president’s health took a downturn after the sudden death of his 12-year-old grandson last May.

In 2003, Mr. Mubarak collapsed during a speech to parliament. The government blamed a combination of cold medication and fasting during the Muslim holy month of Ramadan for the incident.

A year later, Mr. Mubarak reportedly had a minor back operation, also in Germany.

But discussions about Mr. Mubarak’s health are usually kept under tight control by the long-ruling regime and public statements on the issue are rare. In 2006, an editor was sentenced to six months in prison for reporting on rumours about the president’s health. Mr. Mubarak later pardoned the journalist.

The Egyptian leader continues travelling abroad and touring Egyptian provinces. He met with German Chancellor Angela Merkel, on Thursday.

Since taking office in 1981, Mr. Mubarak has not named a successor and never had a vice-president but he is believed to be grooming his son Gamal, to succeed him. Some leaders of the ruling Democratic National Party have suggested that Mr.Mubarak will run for re-election next year.

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