Taking into account the Sunni-Shia divide one can't look at the ME as a bloc because it isn't.
Iran's allies: Russia, North Korea, Lebanon, Syria, China, Kuwait and Iraq.
Saudi Arabia's allies: Pakistan, the U.S, Turkey?
But thing is in case there's a world war, loyalties could shift.
To complicated,take a look.If there had to be a world war who would team up with who and would it stay like that? America is allies with France and England, Russia is allies with China? Who is the biggest allie to the middle east??