One of the most enduring strategic relationships in the Middle East is showing signs of serious strain, after a series of public accusations and diplomatic snubs by Saudi Arabia against its erstwhile ally, America.

The row came to a head this week after King Abdullah, the Saudi monarch, used his opening speech at the Arab League summit to condemn the “illegal” foreign occupation of Iraq and went on to declare that the Arab world would not allow foreign forces to determine the future of the region.

“In beloved Iraq, blood flows between brothers in the shadow of illegitimate foreign occupation and hateful sectarianism, threatening a civil war,” the King told 21 Arab monarchs and heads of state.

The Bush Administration was clearly put out by the outburst from a ruler regarded as a close personal friend by both President Bush and his father. “We were a little surprised to see those remarks,” Nicholas Burns, the US UnderSecretary of State for Political Affairs, told a Senate hearing. “We disagree with them.”

A White House spokeswoman described the Saudi ruler’s statement as “not accurate” and insisted that US forces were in Iraq under United Nations mandate and at the invitation of the Government in Baghdad.

Differences between Washington and Riyadh over Iraq are not new, and the Saudis have made no secret of their displeasure at the treatment of fellow Sunni Arabs in Iraq at the hands of the Shia-dominated Government in Baghdad. But the clash follows a spate of recent incidents suggesting that the damage to the relationship extends beyond this issue.

Last week Prince Bandar bin Sultan, the Saudi National Security Adviser, flew to Washington to offer King Abdullah’s apologies that he would not be able to attend a state dinner in his honour at the White House in April. No reason was offered for the snub.

Observers suggest that the Saudis may simply be distancing themselves from the Bush Administration in an attempt to improve their standing in the region. Traditionally careful not to put their head above the parapet of the region’s politics, the Saudis are now taking the lead in trying to resolve its toughest crises, such as the Arab-Israeli conflict, the stalemate in Lebanon and the war in Iraq. Inevitably this has meant sometimes running against US policy.

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