Recent Iranian airstrikes against Islamic State jihadists in Iraq took place in an eastern region where US warplanes do not operate, the Pentagon said Wednesday, reflecting an accommodation between the two traditional rivals in their fight against a common enemy.

US defense officials said air raids by Iranian F-4 Phantom fighters over the weekend targeting were part of a pattern in which Iranian or American military advisers have carved out separate spheres in Iraq.

“It was in eastern Diyala province,” Pentagon spokesman Col. Steven Warren said of the airstrike. “We have not had any air activity there.” […]