The two countries have had a close strategic partnership since the Second World War.

But for several months the relationship has been marked by mistrust and misunderstanding.

Look at the Saudi and American press and you would scarcely believe the two countries are close allies.

Saudi commentators are describing the bombing of Afghanistan as an act of aggression by a bullying superpower.

US journalists are openly questioning Saudi Arabia's loyalty to Washington - and accusing the Saudi government of fuelling the Islamic extremism which produced the attacks against New York and Washington on 11 September.

Extraordinary letter

Roula Khalaf, of the Financial Times, has just returned from trips to both Riyadh and Washington:

"I think there is a crisis in the US-Saudi relationship, and I think the crisis didn't start on 11 September.

"I think there are a lot of frustrations that have been accumulating over several years - but mainly since the Bush administration took office," she said.

In August, those frustrations led Saudi Arabia's Crown Prince Abdullah to write an extraordinary letter to President George Bush.

It was extraordinary because it warned the American president that unless he actively intervened to resolve the Palestinian issue, the kingdom would review its relations with Washington.

Some thought the letter implied that the Saudis wanted the Americans to remove their troops from Saudi soil.

Gregory Gause, a leading American specialist on the Gulf, said:

"I think that the presence of the American forces in Saudi Arabia - the 5,000 troops at Prince Sultan air base - is an issue the Saudis would like to see resolved.

"But I think in some ways [the events of] 11 September would make the Saudis more reluctant to push on that issue immediately.

"Why? Because if the United States were to evacuate the Prince Sultan air base now, it would be seen by many people in Saudi Arabia and the Middle East as a sign the Saudi-American relationship was crumbling."

That would be a propaganda gift to Osama Bin Laden - the Saudi-born Islamic militant accused of being behind the 11 September attacks - since he has long called for an end to the US military presence in the Arabian peninsula.

War of words

While the issue of the troops remains unresolved, a virtual war of words has erupted between the Saudi and the US media. Othman al-Rawwaf is a member of the 'majlis al-shura' - the unelected body which advises the Saudi government on policy.

He sees a distinction between people-to-people relations and the government-to-government relationship.

"Both sides understand the delicate position of the other concerning this crisis.

" Saudi Arabia understands that the US must act - and the US understands that the position Saudi Arabia is taking is in response to its delicate position.

"It will be difficult. There will be a lot of challenges in the times ahead.

"But I think, in the end, the foundations of the relationship - which was set forth by King Abdel-Aziz and President Roosevelt - will prevail."

It was that meeting between President Roosevelt and Saudi Arabia's first king - during the Second World War - which sealed the new relationship between the two countries.

The relationship has survived because of a mutual need: the Americans need oil, and the Saudis need security.

So can it survive this current crisis?

Roula Khalaf of the Financial Times is thinks it is in the balance:

"I think all depends on what happens over the next few months - whether there is movement on the Arab-Israeli conflict on the part of the Americans.

"It also depends on how long this whole military campaign (against Afghanistan) takes - but also on whether the Americans then move on to a next phase and - as some hawks in the administration are suggesting - bomb Iraq.

"That would be totally unacceptable to the Saudis."