Saudi Arabia's crown prince returned home Friday after a yearlong absence for treatment of an undisclosed illness that sparked rumors about his health and raised questions about the complicated issue of royal succession in the oil-rich kingdom.

Crown Prince Sultan arrived to a royal reception at Riyadh's airport. He looked healthy and shook hands with hundreds of well-wishers led by King Abdullah, his half brother. Sultan joked with the king, and the two kissed and embraced in greetings that were aired live on state TV.

Sultan is one of the most powerful figures in Saudi Arabia. The kingdom's defense minister for 47 years, he closed several multibillion dollar deals to establish the modern Saudi armed forces. He was appointed crown prince in 2005 and is first deputy prime minister.

"I come back to the land of the nation and God has granted me good health," he said upon his return. "I feel happy and exulted and am delighted as I meet the king and the loyal Saudi people."

The 85-year-old crown prince spent just over a year in the U.S. and Morocco for medical treatment and recuperation. He underwent surgery in New York in February this year before going to his palace in Aghadir, Morocco, to recuperate.

He had an intestinal cyst removed in 2004, and diplomats said he has been treated for cancer.

Perhaps in an attempt to demonstrate he has kept up with pressing issues, Sultan spoke briefly about recent floods in the port city of Jiddah that killed at least 119 people, the hajj, the Israeli-Palestinian conflict, Iraq and Afghanistan.

He also mentioned his country's military intervention in Yemen's conflict with rebels that spilled across the Saudi border last month.

The streets of Riyadh were adorned with Saudi flags and pictures of the king and the crown prince in anticipation of his return. Authorities also announced the release of an undisclosed number of prisoners as a gesture to celebrate the crown prince's return.

Shortly after his Nov. 23, 2008, departure from the kingdom, rumors circulated that the crown prince was terminally ill. But family members on several occasions stated that the prince was making good progress and TV footage showed him smiling as he greeted guests in New York and Morocco.

During his absence, Abdullah appointed another half brother, the kingdom's powerful Interior Minister Prince Nayef, as the nation's second deputy prime minister.

Before 2006, whoever held the position was viewed as a crown-prince-in-waiting who would automatically becoming second to the throne.

But in 2006, Abdullah set up the Allegiance Council, a body that is composed of the sons and grandsons of Saudi Arabia's founder, King Abdul-Aziz, who will vote by a secret ballot to choose future kings and crown princes.

The council's mandate will not start until after the reigns of Abdullah and Sultan are over. It is not clear, however, what would happen if Sultan were to die before the end of Abdullah's reign, leaving a question as to whether the council would vote for a new crown prince or whether Nayef would automatically fill that position?

Abdullah, now 90, assumed the throne in August 2005 after the death of his long-ailing half brother, King Fahd. He had already been a de-facto ruler for half a decade and the transition to the leadership of the key U.S. ally and oil giant passed smoothly.