RIYADH, Saudi Arabia, March 28 — King Abdullah of Saudi Arabia told Arab leaders on Wednesday that the American occupation of Iraq was illegal and warned that unless Arab governments settled their differences, foreign powers like the United States would continue to dictate the region's politics.

The king's speech, at the opening of the Arab League meeting here, underscored growing differences between Saudi Arabia and the Bush administration as the Saudis take on a greater leadership role in the Middle East, partly at American urging.

The Saudis seem to be emphasizing that they will not be beholden to the policies of their longtime ally.

They brokered a deal between the two main Palestinian factions last month, but one that Israel and the United States found deeply problematic because it added to the power of the radical group Hamas rather than the more moderate Fatah. On Wednesday King Abdullah called for an end to the international boycott of the new Palestinian government. The United States and Israel want the boycott continued.

In addition, Abdullah invited President Mahmoud Ahmadinejad of Iran to Riyadh earlier this month, while the Americans want him shunned. And in trying to settle the tensions in Lebanon, the Saudis have been willing to negotiate with Iran and Hezbollah.

Last week the Saudi king canceled his appearance next month at a White House dinner in his honor, The Washington Post reported Wednesday. The official reason given was a scheduling conflict, the paper said.

Mustapha Hamarneh, director of the Center for Strategic Studies at the University of Jordan, said the Saudis were sending Washington a message. "They are telling the U.S. they need to listen to their allies rather than imposing decisions on them and always taking Israel's side," Mr. Hamarneh said.