Twilight star Kristen Stewart has had an up close encounter with a royal fan, for the princely sum of $US500,000.

Stewart agreed to meet an unnamed prince for 15 minutes in New York for the exorbitant payment, say reports from the US - including New York Post's Page Six gossip column.

The meeting was negotiated by movie mogul Harvey Weinsten who was approached by the Middle Eastern prince about the chance of a "meet and greet" with his favourite star, Stewart, reports suggest.

Weinstein told reporters at the Toronto Film Festival that Stewart's first response to the request was: "How much?"