Afghanistan's former king, Mohammad Zahir Shah, has flown from Kabul to India's capital, Delhi, for treatment after complaining of intestinal pains.
The Afghan ambassador to India, Massoud Khalili, said doctors had described his condition as stable.
Afghan presidential spokesman Khaleeq Ahmad said the 89-year-old former monarch was tired and had not been feeling well for the past few days.
Zahir Shah returned to Afghanistan in 2002 after 30 years of exile in Rome.
He has played a symbolic but unofficial role in the transition from the ousted Taleban regime to a US-backed administration.
From the newsroom of the BBC World Service