US president Barack Obama's brief encounter with Saudi king Abdullah at the weekend did not produce a meeting of minds or policy changes, but may have reassured Riyadh that Washington remains a firm ally.
Diplomats said the two men discussed "frankly" their "tactical differences" over Iran and Syria with the aim of reducing friction in an alliance forged during the second World War.
On his second visit since 2009, Mr Obama sought to assure the Saudis the US is not pulling back from its traditional regional allies and has no intention of cultivating Sunni Saudi Arabia's rival Shia Iran at the kingdom's expense.
Nuclear deal
During the two-hour meeting at the king's desert camp, Mr Obama assured him the US would not agree to a nuclear deal with Iran that poses a threat to the region but expressed concern over the Saudi intention to transfer shoulder-fired anti-aircraft missiles (Manpads) to Syrian insurgents.
The presence of crown prince Salman bin Abdulaziz and prince Muqrin, recently appointed second in line to the throne, demonstrated that the Saudis had invested a great deal in this event, although substantive talks lasted only an hour.
The issue of involvement in the Syrian conflict has become particularly sensitive. Riyadh has been the major financier and arms supplier to Syrian insurgents and last year pressed six fundamentalist factions to form the Islamic Front, now one of the larger and more powerful opposition alliances.
Syrian insurgents
The US Central Intelligence Agency and its Saudi counterpart have, from bases in Jordan, provided training, arms and logistics support to insurgents in southern Syria. Nevertheless, Riyadh has castigated Mr Obama for failing to conduct air stikes against Syrian army bases in retaliation for last August's poison gas attacks on civilian areas and for refusing to provide sophisticated weaponry to insurgents.
At last week’s Arab summit, prince Salman accused the West of “betraying” the insurgents by refusing to give them arms needed to tip the balance of force in their favour. The US contends Manpads can be transported and fired by a single person and can shoot down warplanes and civilian airliners.
Furthermore, the supply of Manpads to Syrian insurgents would violate international agreements that ban the transfer of Manpads to “non-state actors”.
In spite of Saudi assurances that these weapons would be provided only to "moderate" insurgent groups, the "moderate" secular Syrian rebel groups that emerged in 2011 have, in the past two years, been marginalised by fundamentalist factions. It is likely that Manpads would reach al-Qaeda, which has revived in Iraq.
Women's rights
Before the visit to Riyadh, Human Rights Watch and members of Congress pressed Mr Obama to take up the issue of human rights in the deeply conservative kingdom where women are treated as minors. He did not do so in talks with the king but presented a state department Woman of Courage Award to Maha al-Muneef, a Saudi woman fighting domestic violence.
The choice of Dr Muneef, the director of the National Family Safety Programme, elicited criticism as this is a governmental rather than an independent body and there is no Saudi legislation protecting women from abuse.
