Updated

Defense Secretary Chuck Hagel is promising U.S. allies in the Persian Gulf that negotiations to contain Iran's nuclear program will not weaken their security.

In remarks opening a conference with his Gulf counterparts, Hagel said Wednesday that Washington is hopeful of progress this week in the Iran deal-drafting talks in Vienna.

He said the negotiations "under no circumstances" will trade away Gulf security for concessions on Iran's nuclear program.

Hagel said that regardless of the outcome of the Iran negotiations, the U.S. will remain "postured and prepared" to ensure that Iran does not acquire a nuclear weapon. He said there are about 35,000 U.S. troops in the Gulf region.