Iran demonstrators' "Obama" chant

Nov 4 - Video footage posted on the internet shows Iranian opposition supporters chanting the name of the U.S. President in apparent defiance of security forces warning about "illegal gatherings".

EDITORS' NOTE: Reuters coverage is subject to an Iranian ban on foreign media leaving the office to report, film or take pictures in Tehran

The demonstrators repeat in Farsi: "Obama, Obama, you are either with them or with us."

Some demonstrators are also shown walking over a poster of the supreme leader, Ayatollah Ali Khamenei.

Iran's Revolutionary Guards and their allied Basij militia had warned the opposition not to try to hijack an annual anti-U.S. rally to revive protests against the clerical establishment after June's disputed presidential election.