The proposal, referred to by the diplomats involved as 4+1, may eventually lead to technicians from Turkey, Saudi Arabia, the United Arab Emirates and Jordan working alongside Israelis in joint command-and-control centres.

The US-brokered plan is to build a "moderate crescent" of allied states that share an interest in countering Iran's nuclear ambitions. "The plan is to start with information-sharing about Iran's ballistic missiles," an Israeli official said.

Israel, he said, believed President Barack Obama had no appetite for an attack on Iran's nuclear facilities. "That's why the Americans are working on a regional alliance to deter and contain Tehran," he said. Under the plan, the Israelis would have access to real-time data from radar stations in Saudi Arabia and the UAE.

In return, Israel would provide access to its advanced anti-missile defence systems and early warning radar, which would be shared online with its new partners. Israeli Arrow anti-missile interceptors would shield Jordan against incoming Iranian missiles.

The deal is remarkable, since Saudi Arabia and the UAE have no diplomatic relations with Israel and diplomatic ties to Turkey have been downgraded since the Gaza flotilla raid in 2010, in which eight Turkish activists died.

Mr Obama's initiative to counter the "fundamentalist crescent" of Iran, Iraq, Syria and Hezbollah - the "state within a state" in Lebanon - is seen as ambitious by Israeli diplomats.

"The Americans are trying to get together all the parties who feel threatened by Iran," said Zalman Shoval, a former ambassador to Washington.