Former Israeli Prime Minister Ariel Sharon has been moved to intensive care after developing an infection, the hospital treating him has said.
Ariel Sharon became Israel's prime minister in 2001
Mr Sharon, 78, has been in a coma since suffering a major stroke in January.
"Sharon contracted an infection that is affecting his heart and will receive intensive treatment to combat the infection," the hospital said.
"At this point, his condition is stable," added the statement from the Sheba Medical Center, near Tel Aviv.
Mr Sharon has not regained consciousness since undergoing brain surgery.
His condition has fluctuated throughout the year.
For several months Mr Sharon was treated by the Hadassah Hospital in Jerusalem, where he was rushed for emergency treatment in January.
After several operations on his brain, he was moved from Jerusalem's Hadassah hospital in May to a specialist centre for long-term care.
He subsequently developed pneumonia, and has also undergone kidney dialysis.
Mr Sharon was first elected to the Knesset in 1973 and held a number of cabinet positions before he became prime minister in 2001.
1973: Elected Knesset member for Likud
1975-77: Prime Minister Yitzhak Rabin's special security adviser
1977-81: Minister of Agriculture
1981-83: Minister of Defence
1984-90: Minister of Trade and Industry
1990-92: Minister of Construction and Housing
1996-98: Minister of National Infrastructure
1998-99: Foreign Minister
2001-2006: Prime Minister
2005: Left Likud to found Kadima
A former army commander, as defence minister he masterminded Israel's disastrous invasion of Lebanon in 1982.
He served as housing minister in the early 1990s, expanding Jewish settlements in the West Bank and Gaza Strip, but as prime minister he forced through the 2005 withdrawal of settlers and soldiers from the Gaza Strip.
But while prime minister, he went on to push through Israel's 2005 withdrawal from the Gaza Strip and four settlements in the northern West Bank, despite opposition from within his right-wing Likud party.
He also presided over the building of the controversial West Bank barrier.
Amid growing dissent, Mr Sharon left Likud in November last year to found a new party, Kadima (Forward), which scored a narrow win in the March parliamentary election under Mr Olmert.