John Kerry attends nuclear talks in Switzerland
John Kerry attends nuclear talks in SwitzerlandReuters

The world is "closer than ever" to reaching a comprehensive nuclear deal with Iran, Secretary of State John Kerry said on Monday, according to The Associated Press (AP).

Speaking to a global gathering on nuclear disarmament, where he and Iran's foreign minister met on the sidelines, Kerry warned however that work on a deal is far from over and that key issues remain unresolved.

"I know as well as anyone that we have a long way to go" on the path to a nuclear-free world, Kerry said at the conference, which Israel is attending as an observer. He acknowledged that "we know that we can cut back even further."

Kerry called North Korea "the most glaring example" of ignoring global obligations toward disarmament and said the United States continues to work with partners to set the stage for talks — but only if Pyongyang shows "it's serious."

His comments come as talks continue between Iran and the West on a permanent agreement, after reaching a framework earlier this month.

Global powers must still resolve a series of difficult technical issues by a June 30 deadline for a final deal, including the steps for lifting global sanctions imposed on Iran, and lingering questions over the possible military dimensions of its nuclear program.

Tensions arose after the preliminary framework was reached, as Iran recently accused the United States of "fraud" and "psychological warfare" in publishing a fact sheet announcing what the U.S. claims was agreed on in the framework deal and which an Iranian official called a false translation.

Iran's Supreme leader Ayatollah Ali Khamenei, who will have the final say on any deal, plunged the accord into doubt last week suggesting that "nothing is binding" while President Hassan Rouhani demanded that sanctions be immediately lifted when any deal is signed.