Iran’s Arak heavy water facility. Photo: Wikimedia Commons.

Key restrictions on Iran’s nuclear program imposed under an internationally negotiated deal will start to ease years before the 15-year accord expires, advancing Tehran’s ability to build a bomb even before the end of the pact, according to a document obtained Monday by The Associated Press.

The confidential document is the only text linked to last year’s deal between Iran and six foreign powers that hasn’t been made public, although U.S. officials say members of Congress who expressed interest were briefed on its substance. It was given to the AP by a diplomat whose work has focused on Iran’s nuclear program for more than a decade, and its authenticity was confirmed by another diplomat who possesses the same document.

Read full story at The Associated Press.