Palestinian prime minister Salam Fayyad was hospitalised on Monday with stomach pains, but his life was not in any danger, medics in Ramallah said.
Fayyad "suffered from a mild infection of the stomach and is being treated with antibiotics," a doctor at the hospital in the West Bank city told AFP.
The 61-year-old, a smoker who suffered a heart attack during a private visit to the United States in May 2011, could be kept at the hospital overnight for observation, the source added.
A former senior official at the International Monetary Fund, Fayyad is an economist who won respect for cleaning up the finances of the Palestinian Authority and improving security in the West Bank.
He has headed the Palestinian government since June 2007, after the Islamist Palestinian movement Hamas seized control of the Gaza Strip.
Rumours have been swirling in the past few days that Fayyad is to be removed from the post following a dispute with the nationalist Fatah movement of Palestinian president Mahmud Abbas.
Faced with chronic budget problems, the Palestinian Authority is currently going through one of its worst financial crises since its formation in 1994.