Iran denied any link with explosions in Bangkok and accused "elements linked with the (Israeli) Zionist regime" of being responsible, state TV said on its website on Wednesday.
Foreign ministry spokesman Ramin Mehmanparast rejected "the accusations by the Zionist regime of implication (of Iran)", accusing Israel of "trying to harm the friendly and historic relations between Iran and Thailand."
"The Islamic Republic of Iran believes that elements of the Zionist regime are responsible for this crime and is prepared to help and cooperate with the Thai government to shed all light on these events," he added.
Mehmanparast noted that Israel's accusation followed US allegations last October of a Tehran-hatched plot to assassinate the Saudi ambassador to Washington, and Israeli claims Tehran was behind bomb attempts against Israeli diplomats in India and Georgia on Monday.
He termed both those other accusations "baseless".
Thai authorities were holding two Iranians in connection with a series of explosions in Bangkok on Tuesday.