Jalal Talabani, the Iraqi president, is in "stable condition" having suffered a stroke and a hardening of his arteries this morning, officials have said.
Talabani is being treated in the intensive care unit of a Baghdad hospital after being rushed there on Tuesday morning, a statement from his office said.
"Tests show that his bodily functions are normal and his excellency's condition is stable," the statement said. "He is under intensive medical supervision."
Earlier, a statement from Talabani's office said that he had suffered a "health emergency".
The Iraqi president has struggled with various health problems in recent years. He underwent successful heart surgery in the United States in August 2008.
A year earlier, he had to be flown to neighbouring Jordan to be treated for dehydration and exhaustion. He has also travelled to the United States and Europe for treatment for a variety of ailments.
Talabani survived wars, exile and in-fighting in northern Iraq to become the country's first ever Kurdish president a few years after the 2003 invasion that toppled Saddam Hussein.
The Iraqi presidency is a largely ceremonial post, though it does retain some powers under Iraq's constitution.