Australian officials say that the acting president of the tiny Pacific island of Nauru, Derog Gioura, has had a heart attack and is in hospital in Australia.
An Australian government spokeswoman said that Mr Gioura's condition was not life-threatening.
She said that Mr Gioura - who was appointed acting president after his predecessor, Bernard Dowiyogo, died last month - would remain head of the caretaker administration until elections due to be held in May.
Nauru, a 21 square kilometre island, is home to 12,000 people.
It is heavily dependent on Australian support, after millions of dollars from its one major industry, phosphate mining, were lost in failed investments.