In a statement read on state television, the king said he was warning the world, particularly the United States, that "if the option of peace fails as a result of Israeli arrogance, then the only option remaining will be war, and God alone knows what the region would witness in a conflict that would spare no one."
The king has decreed donations totalling 1.5 billion to Lebanon, said the royal court statement. The king has assigned $500 million for the reconstruction of Lebanon, and $1 billion to be deposited in Lebanon's central bank to support the economy.
Abdullah also ordered a grant of $250,000 to the Palestinians, the statement said. Israel has conducted a military campaign against the Gaza Strip since shortly after Palestinian militants kidnapped an Israeli soldier from inside Israel on June 25.
The king said that the Saudi government had been trying to bring a halt to the violence since it began on July 12, when Hezbollah guerrillas snatched two Israeli soldiers in a cross-border raid from Lebanon.
More than 390 people have been killed in Lebanon during the past 14 days and another 600,000 Lebanese displaced. More than 40 Israelis have been killed, many in Hezbollah rockets attacks on northern Israel.
"It must be said that patience can't last forever, and if the brutal Israeli military continues to kill and destroy, no one can foresee what may happen," the king said.
Saudi Arabia, Egypt, Jordan and Kuwait have rebuked Hezbollah for the fighting in Lebanon, where The Saudis described the kidnapping of the two Israeli soldiers as an "uncalculated adventure."
The king's talk of "Israeli arrogance" will find broad appeal in the Arab street, where many people have accused their governments of doing nothing to stop the assault on Lebanon.
Critics have said the Saudi criticism of Hezbollah encouraged Israel to attack the militant group. Abdullah's comment Tuesday appears intended to distance the kingdom from that charge.
The king was expected to discuss the Lebanese-Israeli crisis with Egyptian President Hosni Mubarak, who was due to arrive in the kingdom later Tuesday.
Abdullah's statement comes a day before the kingdom takes part in an international conference on the crisis in Rome, which is scheduled to draw U.S. Secretary of State Condoleezza Rice and numerous Western and Arab envoys.
Jordanian Foreign Minister Abdul-Illah al-Khatib said Tuesday that the Arab delegates would push for two points in Rome — an immediate cease-fire and the Lebanese government's assertion of its authority over southern Lebanon, where Hezbollah guerrillas have long been in control.