The singer confesses backing the initial decision to remove Saddam Hussein from power - but was "shocked" when it was revealed a dossier detailing Hussein's possession of weapons of mass destruction was exaggerated by the British Government.
He says, "At the time of the Iraq invasion, "I was ambivalent; getting rid of Top of Saddam Hussein was a gift for humanity and I thought that there was a coherent plan to put Iraq back on its feet. (But it) shocked me to know that Blair already knew that the weapons of mass destruction were simply an excuse and that there was nothing planned for the day after (the invasion)."
Jagger also fears much for the future of Iraq - still the site of much conflict two years after Hussein's regime was toppled.
He adds, "If we do not take intelligent steps, a part of Iraq will end up becoming an Islamic republic, a puppet of Tehran."
Last month Jagger hinted one of the band's new songs, SWEET NEO CON, is a critique of US President George W Bush's regime.