Saudi King Abdullah has reportedly undergone a successful back operation in New York.
Dubai-based Al-Arabiya television reported Wednesday that the king's health has notably improved following the surgery, after a blood clot complicated a slipped disc.
A Saudi diplomat told the Associated Press the king's surgery took place at New York Presbyterian Hospital.
The 86-year-old monarch left for the United States Monday, temporarily handing over duties to the Crown Prince Sultan.
The health of King Abdullah has raised the question of who will succeed him.
Both the king and crown prince are in their 80s and have suffered health problems in recent years. Crown Prince Sultan, who is also the defense minister, has been convalescing in Morocco and returned to Saudi Arabia just prior to the king's departure.
Analysts say after the crown prince, the 76-year-old Deputy Prime Minister Prince Nayef could most likely be the next ruler.
Since the creation of modern Saudi Arabia in the 1930s, sons of its founder, King Abdul-Aziz, have ruled the kingdom.
Any transfer of power is expected to have worldwide implications, as the country controls a large portion of the world's oil and is a key U.S. ally in the fight against Islamic militancy.
Some information for this report was provided by AP and Reuters.