The decision of the appointment was announced by the royal court in a statement issued on Tuesday, saying “We deputise, according to our order, Crown Prince Salman to manage state affairs and oversee the interests of the people during our absence from the kingdom.”
The brief statement did not say where King Abdullah, who is 89, had gone, or how long he was expected to be abroad in a country where the health of senior royals is keenly watched.
Salman was appointed Abdullah’s heir in June after the deaths of two crown princes, Sultan and Nayef, in eight months.
The role of crown prince does not just mean Salman would inherit power after Abdullah’s death, but makes him the king’s deputy in wielding executive power.
Salman, who is also Saudi Arabia’s Defence Minister, served as governor of Riyadh province for about five decades. Diplomats say he will likely continue Abdullah’s cautious economic and social reforms when he becomes king.
Two weeks ago, King Abdullah appeared in good health hosting a summit conference for Muslim countries in Makkah, where he briefly stood to welcome each arriving leader and chatted between greetings with Iranian President Mahmoud Ahmadinejad.