Saudi Arabia's Crown prince Sultan bin Abdul Aziz salutes to a Honor Guard upon his arrival to the government airport Vnukovo II, outside Moscow 21 November 2007. Saudi Arabia's crown prince is on official visit to Russia for talks that could pave the way for Riyadh to buy Russian weapons for the first time. Prince Sultan bin Abdul Aziz, who doubles as defence minister, was invited to Moscow by President Vladimir Putin after the Russian leader visited oil-rich Saudi Arabia in February, the diplomat told.