Saudi prince health signals possible tussle for power

By Andrew Hammond

RIYADH, May 4 (Reuters) - Saudi Crown Prince Sultan's visit to a Swiss clinic for medical checks last week provided a reminder of a potential power vacuum in the world's biggest oil exporter, analysts and diplomats say.

The official news agency SPA carried pictures of a healthy-looking prince smiling on Friday, appearing to lay to rest for now concerns that his health was failing.

Sultan, in his early 80s, had an intestinal cyst removed in Saudi Arabia in 2005 and diplomats say he is in weaker health than King Abdullah, who is thought to be in his mid-80s.

Sultan went straight from a holiday in the Moroccan resort of Agadir -- a royal favourite -- to Geneva where he stayed most of last week for "regular medical tests".

The large retinue of family and friends that travelled to Geneva to see him, according to Saudi media, raised concerns that the tests may be more than routine.

A government official said well-wishers simply took a chance for direct access to the prince outside Saudi Arabia, where protocol and affairs of state limit the scope for an audience.

But the brief Geneva sojourn highlighted potential instability in the country, a key U.S. ally and strict Islamic state, over who among the Saudi royal family will take the reins of power after the era of King Abdullah and his heir Sultan.

There is no designated second-in-line to the throne, and since coming to power in 2005 King Abdullah has set up an "allegiance council" of sons and grandsons of the kingdom's founder to regulate the affairs of the succession.