Fantasy, adventure, middle eastern setting, read in 2000s, young man, mage/sorcerer, princess I think, trying to defeat tyrant leader

[Janice]

I don't remember a lot about this book. I think it was a stand alone, I got it from the children's library when I was in middle school in the early 2000s, it was a decent sized novel, I think the cover was mainly white, beige, or some other neutral color. I don't remember much more of the plot or characters, other than I think the 3 main characters traveled a lot, and that the man and mage meet the girl along the way and don't find out who she is until later. I don't know for sure she's a princess but I'm pretty she's super important to the land they're trying to save from the tyrant leader or whomever. It's set somewhere middle eastern, my vague memories give me the feel of India or Persia or something.
I do remember one specific scene where they're trying to get into somewhere, and she uses magic she learned from the mage/sorcerer guy to slow her heartbeat enough to trick the guards into thinking she is dead.

[Merannda]

Guess for you ... The Akhenaten Adventure

[Abigail]

Closest I know of (a sort of Arab/beduin feel, more than Indian, though-lots of desert, and both she and he have powers) - both are by Robin McKinley:

The Hero and the Crown

The Blue Sword