The Twilight actress agreed to meet the unnamed royal in a brief encounter in New York, on the condition that the hefty sum would be donated to charity.
The meeting was arranged by Harvey Weinstein, and according to the movie mogul, the first question Kristen asked about the deal was, "How much?"
Each minute spent with Kristen cost the Arab royal an estimated £21,000, which roughly works out at an unbelievable £350 a second.
The Arab prince reportedly paid the £315,000 in cash before he got to meet the intriguing actress. Kristen, who was accompanied by her team of bodyguards, generously donated the funds to the Hurricane Sandy relief effort.
Harvey made the revelation at the screening of his Hurricane Sandy benefit concert documentary 12.12.12. The 15-minute sit down reportedly took place at Madison Square Garden in December of last year.