Name for a person who hires an assassin/hitman

[drross]

Is there a word to describe this person? A work colleague (from Italy) describes the person as a mandator but this doesn't quite fit for English.
Any ideas?

[sir.prize]

okuri

[sir.prize]

and . . .

the person who hires an assassin is called an okuri, and the go-between from the okuri to the assassin (so the instigator is left anonymous) is called a motojime

[drross]

I take it these are Japanese derivatives (not in Chambers). Nothing from English?

[sir.prize]

Afraid not drross [:(

[jno]

it's probably to Britain's credit that its language does not have a word for such people. You can see why Italian has.

[JonnyBoy12]

The President of the United States of America!

[Quizmonster]

Sir.prize's second response above uses the word instigator. Interestingly, one of the illustrations of that word in The Oxford English Dictionary contains the words, "the chief instigator of the murder". Of course, one may instigate without hiring, but I'd say it's pretty close to the word you actually want.