President Bush backed his political rhetoric against Iran yesterday with the promise of a $20 billion arms deal to boost the military clout of Washington’s key allies in the Gulf.

The deal, which could still be blocked by Congress, would see weapons, including Patriot missiles and precision-guided bombs, parcelled out to Gulf states, including Saudi Arabia, to counter Iran. The announcement was timed to coincide with Mr Bush’s arrival in Riyadh, where he sought further support from King Abdullah for his continuing campaign against the Islamic Republic.

However, the President’s central message of his Middle East tour – that Gulf States need to confront Iran – has so far failed to gain much traction in this troubled region.

The Sunni-majority countries that have played host to the President so far are intensely wary of Iran’s ambitions, but are also sceptical about Mr Bush’s estimates of its nuclear capabilities. While most of the Arab leaders who have met the President expressed cautious optimism over his latest attempt to broker a peace accord between the Israelis and Palestinians, they have remained silent on Iran.

The arms sale is seen as key to Washington’s strategy of shoring up support for its efforts to isolate Tehran. However, it is unclear how far Gulf states would go in backing Mr Bush at the risk of antagonising Iran.

“Nobody’s going to back any kind of military action. Everybody knows Iran is just too big. This is not our agenda,” said Abdulkhaleq Abdullah, a professor of political science at Emirates University in the UAE, where Mr Bush delivered his keynote speech on Sunday.

Under the deal, Saudi Arabia is set to receive $9 billion (£4.5 billion) of weapons. King Abdullah delivered a diplomatic coup for Mr Bush when he attended the Annapolis talks with Israel last November. However, observers predicted that the two leaders could clash in current talks. Saudi Arabia opposed the 2003 US-led invasion of Iraq and opposes a strike on Iran.

Mr Bush spoke out recently against a Saudi court verdict condemning a gang-rape victim to 200 lashes. The criticism was regarded as contributing to King Abdullah’s decision to issue a pardon to the 19-year-old woman.

King Abdullah, a notorious night-hawk invited Mr Bush to his palace for a 9pm meeting, which is said to be when the President normally turns in. Asked by a reporter if the meeting was the latest ever attended by Mr Bush, Steve Hadley, the National Security Adviser, replied: “I don’t know. It sort of depends on which time zone – are we on Washington time? Are we on Saudi time? I don’t know.”

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