The disclosure by the Israel-friendly Wall Street Journal that the Obama Administration is preparing to sell advanced Boeing F-15 fighter jets to Saudi Arabia should not come as a major surprise. In recent months there have been unconfirmed reports in the American and Israeli media that a deal of this kind was in the offing. Nevertheless, it will lead to anxiety in Washington, Jerusalem and beyond.
In recent years the US has eschewed the sale of modern weapons systems to Saudi Arabia out of deference, among other things, to the Israel lobby on Capitol Hill. As a result the Saudis have looked towards the UK for their military supplies, with BAE, an authorised arms supplier to the Pentagon, in the pilot's seat. The British arms supplier's contract to provide 72 Eurofighter (Tornado) jets to Saudi Arabia (a deal which sparked now-settled corruption allegations on both sides of the Atlantic) was part of the this arrangement.
Despite the involvement of Saudi nationals in 9/11, the US attitude towards selling Riyadh advanced weapons systems has been changing. As President Obama's initial enthusiasm for reaching out to Iran has cooled, so has the determination of Washington to bolster the defences not just of Saudi Arabia but of neighbouring Gulf states too.
Not surprisingly, Israel has reservations. These surfaced in a report on the American news agency UPI - itself regarded with some scepticism since it fell under the control of the Moonie-controlled enterprise, News World Communications, a decade ago.
UPI reported last month that Israel was seeking to prevent the sale of advanced model Boeing F-15s to the Saudis. The matter had been raised by Ehud Barak, the Israeli defence minister, who was described as having a "high" standing in Washington where he is seen as a counterweight to Prime Minister Netanyahu.
The Wall Street Journal article described the proposed 10-year accord as being worth $30bn and one of the "biggest single deals" of its kind. Israel has an understanding that the US will refrain from making arms sales to its near neighbours which would, in any way, undermine the Jewish state's technological edge in the region.
What has worried Israel this time, according to reports in the Israeli and American press, is the scale of the agreement. It involves 84 aircraft, all of which will be fitted with on-board targeting systems offered to other foreign governments.
Israel reportedly has decided it would not oppose the Saudi sale after it was agreed that the Pentagon would not supply long-range weapons which can be used for offensive land and sea based targets. The likely deciding factor for Barak, who has been the point man for the negotiations, is an apparent commitment by the US that Israel will be provided with access to the new F-35 Joint Strike Fighter which is being developed by Lockheed Martin and will be ready for delivery in 2015. It is a far more advanced plane than the now ageing F-15 and can perform air support and tactical bombing missions.
Normally, when the Israeli government tacitly gives its support to arms packages to Arab states, the pro-Israel lobby desists from opposing the deals, which have to be approved by Congress. However, in the run-up to the mid-term elections and the 2012 presidential election, it is easy to imagine that an arms order to the Saudis on the scale proposed could lead to bitter fight on Capitol Hill. The lobby may be concerned that the deal changes the balance of power in the region and erodes Israel's edge.
Saudi Arabia is not likely to have helped itself in Washington by its ill-judged effort (widely reported on the BBC website) to block the messenger function on BlackBerry handsets, fearing they could be used by the Americans to snoop on them. The proposed ban has now been ditched but it provides a reminder that US-Saudi relations do not always run smoothly.