Brett McGurk, the National Security Council coordinator for the Middle East and North Africa, told the annual Manama Dialogue conference in Bahrain that his country is focused on deterring "imminent threats" in the strategic energy-rich and conflict-ridden region.

"The United States is now actively building and enabling an integrated air and maritime defence architecture in this region", said McGurk, the top White House official on the Middle East.

"Something long talked about is now being done, through innovative partnerships and new technologies", he added without elaborating.

On Saturday, the US Central Command chief General Michael Kurilla announced during the same conference that a US-led task force will deploy more than 100 unmanned vessels in the Gulf region's strategic waters by next year to stave off maritime threats.

The announcements came after Israel and the United States blamed Iran for a drone strike off the coast of Oman last week that hit a tanker operated by an Israeli-owned firm.

The attack, which coincided with heightened tensions between Tehran and Washington, was the latest in a string of disruptions in Gulf waters that are a major route for world energy supplies.

McGurk said the US forces have "exposed and deterred imminent threats" by Iran, confirming earlier reports that the Islamic republic was planning an attack against its regional rival Saudi Arabia.

"That attack likely did not emerge because of the close security cooperation between Saudi Arabia and the United States, which is ongoing and continuous", he explained.

Speaking at the same session, the Israeli National Security Adviser Eyal Hulata described Iran as Israel's "most prominent security threat".

Israel has lobbied the United States and main European powers to abandon attempts to renew a 2015 deal with Tehran over its nuclear programme.

Negotiations over that deal have stalled.

"Enough with futile talks in Vienna", said Hulata, adding that "even the people of Iran are saying enough" as it embarks "on a brutal crackdown against its own people".

He was referring to the two months of nationwide protests which have become the biggest challenge to Iran's clerical regime since the country's 1979 Islamic revolution.