British Foreign Secretary Philip Hammond
British Foreign Secretary Philip HammondReuters

British Foreign Secretary Philip Hammond said late Sunday he believed a nuclear deal with Iran could be reached, but insisted it must place an atomic bomb "beyond reach" for the Islamic Republic, reported AFP.

"We are here because we believe a deal can be done," Hammond told reporters outside a Lausanne hotel as he became the last of the foreign ministers to arrive for talks with world powers.

"It's in everyone's interests that a deal does get done. But it has to be a deal which puts the bomb beyond Iran's reach," he added.

"There can't be any compromise about that," Hammond insisted.

He went straight into a meeting with ministers from the other P5+1 powers -- China, France, Germany, Russia and the United States.

Hammond said on Friday he was ready to join the talks in Lausanne, but added he would only fly to Switzerland if there was an immediate prospect of progress.

His comments on Sunday come hours after reports emerged that a provisional agreement on key elements of Iran’s nuclear program had been reached.

Western diplomats in talks in Switzerland said that Iran had "more or less" agreed to slash the number of its centrifuge machines “by more than two-thirds” and to ship abroad “most of its stockpile of nuclear material.”

Israeli Prime Minister Binyamin Netanyahu has said the deal currently under discussion between Iran and world powers over Tehran's nuclear program is even worse than he had feared.

"The dangerous accord which is being negotiated in Lausanne confirms our concerns and even worse," Netanyahu said in remarks at a meeting of his cabinet broadcast on public radio.

Netanyahu also highlighted concerns over Iran's wider expansionist ambitions in the region via Shiite Islamist proxies and other terrorist groups.