Mossad chief Meir Dagan is expected to brief Britain's MI6 head Sir John Scarlett, who is slated to visit Israel later this month, on an intelligence breakthrough regarding the Iranian nuclear program, London's Sunday Times reported. Concern has been mounting in Israel that Iran's nuclear capability may be far more advanced than was recognized by the US National Intelligence Estimate last December, which reported that Iran had halted its nuclear weapons development program in 2003 in response to international pressure. A source quoted by the paper on Sunday claimed that the new information was on par with intelligence that led to the discovery and destruction of a partly constructed nuclear reactor in Syria last September. Israeli officials believe the US will revise its analysis of Iran's program. "We expect the Americans to amend their report soon," a high-ranking military officer said last week. Foreign Minister Tzipi Livni briefed British Prime Minister Gordon Brown and Foreign Secretary David Miliband on Israel's findings during talks on the Middle East in London last week. Israeli intelligence officers, en route from Washington where they had been outlining their latest information to American officials, joined Livni for the briefing. It is believed that if Israel were weighing military action against Iran, it would first seek diplomatic support in London and Washington because of the danger of triggering a wider Middle East conflict. "We're doing a lot of things about Iran," Defense Minister Ehud Barak said last week. "We say we shouldn't rule out any option. Not ruling out options means action, but the worst thing to do at the moment is to talk [about it]."