The president of Yemen, Ali Abdullah Saleh, has warned that any attempt at a military coup will lead to civil war.
He said he would step down by January next year, but only after organising parliamentary elections.
His offer was rejected by the Yemeni opposition, which wants him to leave immediately.
President Saleh faces a threat from a growing protest movement which in the past few days has been joined by generals, ambassadors, tribal leaders and other senior officials.
Gregory Johnsen is an expert on Yemen at Princeton University.
First broadcast 22 March 2011