BEIRUT, Lebanon - Lebanon's new president got a red-carpet welcome yesterday, but was quickly thrust into the political thicket as Hezbollah's leader warned against any efforts to disarm the Iranian-backed guerrilla group.

Sheikh Hassan Nasrallah delivered his stern message after military bands and an honor guard had saluted President Michel Suleiman on his first day on the job.

Suleiman, the former army commander, was a consensus candidate agreed on by both Hezbollah and its pro-Western political foes, but he drew pointed comments from Nasrallah after saying in his inauguration speech Sunday that there should be a dialogue over Hezbollah's arsenal.

The Shiite extremist group has rejected demands to disarm, insisting its weapons are needed to protect Lebanon from Israel.

Nasrallah's speech was his first since Hezbollah fighters seized several areas of Muslim West Beirut in fighting this month, forcing the Western-backed cabinet to agree to a political deal designed to give Hezbollah and its allies a veto over government policies.

The Hezbollah leader pledged to comply with a provision of the Arab League-brokered agreement that forbids the use of arms to achieve political gains. But he warned that the government should not try to use the military against Hezbollah and its allies.

"The resistance weapons should not be used to achieve political gains," Nasrallah told tens of thousands of supporters crowding a playground in South Beirut. He spoke by video link from a hiding place.

At the same time, he said: "The state's weapons should not be used to settle accounts with an opposition political party, or in favor of outside parties that weaken Lebanon's strength and immunity in confronting Israel."