He also said that Iran and Syria are conducting a "coup" against his government, since they have provided arms to Lebanon's Hizballah party.
Siniora told "Focus" that the "Iranians say they want to defeat the U.S." and demanded that Lebanon not be used as the battlefield.
Deadly violence in Lebanon, following a call by the Shi'ite Hizballah for a general strike on January 23 to pressure the government, has renewed fears that the country could slide into civil war like the conflict that devastated it in 1975-90.
A Hizballah-organized sit-in outside Siniora's downtown offices is nearing the start of its third month.
Hizballah is demanding that Siniora give it one-third of the seats in his cabinet and call early elections.
Iranians demonstrating in support of Hizballah in Tehran on July 17 (epa)
'FOR THE SAKE OF LEBANON': The Islamic Republic of Iran has served as an ideological inspiration for Hizballah since the Lebanese militant group's creation in 1982, and Tehran acknowledges that it supports the organization morally and politically. "Yes, we are friends of Syria and Iran" Hizballah leader Hassan Nasrallah has said. "For 24 years we benefited from our friendship with Syria and Iran for the sake of Lebanon...." (more)