UNITED NATIONS — Warning against the undermining of Palestinian Arab rights by “bullying and corrupt powers” in the West, President Ahmadinejad of Iran yesterday expressed his support for Hamas, apparently attempting to counterbalance the Western rush to reshape the region.

Mr. Ahmadinejad’s verbal attack on the regional and international supporters of Hamas’s rival, the Fatah Party of the Palestinian Authority’s President Abbas, came just as American officials confirmed that the outgoing British prime minister would be named today as top envoy to the Palestinian Arab-Israeli dispute.

“Anybody who cares about greater peace and stability in the world knows that a lasting and enduring resolution of the Israeli-Palestinian issue is essential, and, as I have said on many occasions, I would do whatever I could to help such a resolution come about,” Prime Minister Blair told London reporters.

But as Mr. Blair spoke of peace, weapons continued to flow into the region.

A new U.N. report concluded that border controls were “insufficient” to prevent arms smuggling into Lebanon from Syria, and President Mubarak of Egypt indicated in an interview with an Israeli newspaper that it was all but impossible to end weapons smuggling into Gaza. According to Israeli and American intelligence assessments, Iran is a leading power behind the weapons smuggling industry in Lebanon and Palestinian Arab territories.

“Palestine is a mirror which reflects all characteristics of ambitious powers,” Mr. Ahmadinejad said yesterday in Tehran, according to the Iranian news agency IRNA. “Today, not only those who obviously carry the banner of opposition to Islam, but liars who are hiding under cover of piety are being tested in Palestine.”

“These bullying and criminal powers,” he said, “ousted the democratic government in Palestine and installed their own stooges. They intend to decide fate of the people.”

“The Palestinian case does not belong to the Palestinian people alone, rather it belongs to all human society,” he added, “If the crimes of these powers continue in Palestine, the criminals will take a major step towards death.”

According to an assessment team sent to Lebanon by the Security Council, “vehicles, including passengers and their cargo, pass freely” between Lebanon and Syria. “The present state of border security was insufficient to prevent smuggling, in particular smuggling of arms,” the team’s report that was published yesterday said.

A separate U.N. report recently detailed how those weapons find their way into Palestinian Arab camps in Lebanon, where shady pro- Syrian and pro-Iranian groups use them to foment violence. Another U.N. report, on the implementation of the resolution that ended last year’s Lebanon war, is expected today.

Signaling that he now realizes unauthorized weapons threaten his control over the West Bank, Mr. Abbas yesterday issued a presidential writ banning all unauthorized weapons there. But members of an armed militia loosely affiliated with Fatah, the Al Aqsa Brigades, announced they would not disarm.

Rather than fight Hamas, Fatah’s regular security forces recently fled Gaza. Fatah had failed to disarm Hamas in Gaza, but according to Mr. Mubarak, even Israel was unable to end the flow of weapons when it controlled the strip.

“Were you able to end smuggling when you controlled” Gaza? Mr. Mubarak asked in Yediot Achronot yesterday. “They are crafty,” he said, referring to the smugglers who cross the Gaza border with his country, known as the Philadelphi Corridor. “They dig tunnels even under closets in homes. How can you discover that?”

Addressing his Israeli critics, Mr. Mubarak said it was in Cairo’s interest to end the weapons smuggling. Last year, he said, Egypt blew up 68 cross-border tunnels, and confiscated three tons of explosives.