Two of the United States’ closest allies in the Middle East, Israel and Saudi Arabia, are on the brink of signing large arms deals with the US in a move designed to ratchet up the pressure on Iran, according to defence analysts.

 

America has agreed to sell Saudi Arabia 84 of the latest model of the F-15 jet and dozens of Black Hawk helicopters. The deal also includes refurbishing many of the kingdom’s older F-15s, the Wall Street Journal reported on Monday.

 

Israel is believed to have opposed the $30 billion deal. However, in a concession to Israel, the new F-15s, made by the Boeing Company, will not be equipped with the latest weapons and avionics systems available to the US military.

 

The last such major arms sale by the US to Saudi Arabia was in 1992, when the kingdom received 72 F-15s. On that occasion, Israel tried to block the $9bn deal by lobbying the US Congress, straining relations with the White House of George H W Bush.

 

Meanwhile, the US is preparing to provide Israel’s air force with the F-35, the latest jet fighter made by Lockheed Martin, the Israeli daily Haaretz reported last week.

 

The F-35’s stealth technology, which allows it to evade radar detection and anti-aircraft missiles, comes with a hefty price tag of up to $150 million a plane -- a cost that Israel had been balking at.

 

But, according to the reports, the US has offered Israeli firms defence contracts worth $4bn to supply parts for the F-35 -- a deal some Israeli analysts believe is designed to buy Israel’s silence over the Saudi deal and ensure it gets through the US Congress.

 

It is one of the largest such deals in Israel’s history and it would offset much of the cost to Israel of buying its first batch of F-35s.

 

The aircraft is not expected to enter service until 2014. If Israel signs up for a single squadron of 20 F-35s, as expected in the next few weeks, it would be the first country outside the US to secure the jet. Israel has been given an option to buy 55 more.

 

Last year Israel had threatened to abandon negotiations over the F-35 and opt instead to buy the advanced F-15. Saudi Arabia’s reported purchase of that jet appears to make such a scenario less likely.

 

The Obama administration has faced heavy lobbying from Israel to prevent the sale of the F-15s to Saudi Arabia.

 

“Today these planes are against Iran, tomorrow they might turn against us,” Haaretz quoted an unnamed security official as saying last month.

 

Ehud Barak, Israel’s defence minister, told the Washington Post last month that the US administration was committed to making sure Israel was not left in an “inferior situation” and was “doing a lot to support Israel’s qualitative military edge”.

 

The Saudis have become one of the largest purchasers of US-made arms since they bought the first AWACS surveillance planes in the 1980s. According to a recent Congressional report, the Gulf kingdom spent $36 billion world-wide on arms in the seven years to 2008.

 

Today, Saudi Arabia has the third largest air force in the Middle East behind Israel and Iran. The Royal Saudi Air Force has 280 “combat capable” aircraft, according to data compiled by the Center for Strategic and International Studies, compared to Israel’s 424 and Iran’s 312.

 

The Wall Street Journal did not specify the model of F-15 being bought by Riyadh, but experts widely assumed it to be the upgraded Strike Eagle. The jet, designed for precision air-to-surface attacks, was the main one used by the US in destroying Iraq’s radar and missile systems during the 2003 invasion.

 

Analysts said the joint strengthening of the Saudi Arabian and Israeli militaries was seen as a key regional interest for the US, given the belief in Washington that Iran is seeking to develop a nuclear warhead and is rapidly amassing a large arsenal of missiles.

 

If, as Iran reportedly claimed last week, it is in possession of Russian S-300 anti-aircraft missiles, the F-35 stealth technology would give Israel an important advantage in an attack.

 

However, some analysts have questioned the wisdom of the US arms sales.

 

Trita Parsi, an analyst at the Woodrow Wilson Center in Washington and an expert on Israeli-Iranian relations, said it was a “misguided policy” aimed at keeping Tehran “isolated and subdued”.

 

“All that is achieved by heavily arming Arab states and Israel is to increase Iran’s sense of insecurity and therefore make the region less secure,” he said.

 

Stephen Zunes, a US-based Middle East policy analyst, accused Washington of setting the stage for another “arms race” in the region.

 

“This is a pattern we’ve seen before. The US offers Arab states expensive modern armaments, and then turns around to Israel and tells it it needs to have even better weapons to stay ahead in the race. Then the pressure again mounts on the Arab states. It’s a racket that has been a bonanza for US arms manufacturers,” he said.

 

Israel receives $3bn annually in US military aid, more than any other country and covering about a quarter of Israel’s defence expenditure. Unlike other recipients, Israel is allowed to spend 26 per cent of the aid on the development and production of its own weapons systems.

 

However, Israeli officials are reported to fear that a combined squeeze on the country’s defence budget and a massive outlay on buying a large number of F-35s would leave the military without money to replenish its stocks of ammunition and bombs.

 

Last month Washington agreed to an additional military subsidy of $420 million to help Israel develop its “missile shield” programmes, designed to intercept short-, mid- and long-range missiles.

 

Israel has been concerned by the growing stockpiles of rockets and missiles that Hamas and Hizbullah have accumulated close to its borders as well as the more advanced arsenals of Iran and Syria.

 

In addition to the question of the price of the F-35, Israel and the US have been at loggerheads over whether Israel should be allowed to install its own avionics and weapons systems. So far the US has refused, and last month denied Israel a test aircraft.

 

In the past, Tel Aviv and Washington have fallen out over Israel copying and selling on American systems to other regimes.