Buddhist monks spearheading Burma's biggest anti-government marches in nearly two decades defied orders from the military junta to stay out of politics and relaunched their protests in the country's two biggest cities today.

The US is poised today to impose additional sanctions against Burma's military rulers after they issued a veiled threat to suppress pro-democracy demonstrations.

Monks leading the biggest public protest staged in Burma for nearly 20 years were today warned of a government crackdown.