THE WORLD - Ties tense among Arab nations - Recent squabbles between Saudi Arabia and Syria highlight growing differences. Iran has many on edge.

Iran's backing of Hezbollah in Lebanon and Hamas in the Gaza Strip, along with its nuclear program, volatile hard-line president and support of a conservative Shiite-controlled Iraq, have unnerved Middle East politics. The atmosphere has been further agitated by Syria's growing bond with Iran, which has incensed Saudi Arabia and other Sunni Arab nations.

Iran and Syria have similar interests in keeping the atmosphere on edge, especially in Lebanon, where the Sept. 25 presidential election is a backdrop for wider regional ambitions. Iran hopes that Lebanon's Hezbollah opposition can establish a Shiite government in the midst of the Sunni world, and Syria, fearful of losing stature among its neighbors, is desperate to keep a hand in Beirut's affairs.

"The real challenge is that the bloc of moderate governments in the Middle East lacks credible leadership to counter the radical states Iran is attempting to consolidate," said Gamal Abdel Gawad, an analyst with the Al Ahram Center for Political and Strategic Studies in Cairo. "Saudi Arabia tried to act as a unifying Arab voice, but it overestimated its ability. There are limits to what checkbook diplomacy can do."

Insults swapped last month between Syria and Saudi Arabia are the most recent bitterness inflaming the Arab media. It began when Damascus said Riyadh's unsuccessful attempts to mediate the unrest in the Palestinian territories have shown that the Saudi regime is "semi-paralyzed."

The Saudis were outraged and accused Syria and Iran of provocation across the Middle East. "The problem is not in the positions of the kingdom, but in the positions of those who broke with Arab ranks and those responsible for spreading chaos in the region," a Saudi government statement said.

Syrian Foreign Minister Walid Moallem is expected to meet with Saudi officials today to calm matters. But the underlying sentiments characterize a Middle East that is at once petty and increasingly dangerous. The unpredictability of Lebanon, the war in Iraq and the political victories of Hezbollah and Hamas have underscored Syria's break with its Arab neighbors and the centuries-old Shiite-Sunni divide. Highlighting both the seriousness of the day and the region's squabbles was an earlier Saudi boycott of a conference on Iraq sponsored by Syria.