The President of Yemen, one of America's foremost allies in the "war on terror", has become the latest leader in the Middle East to announce he will be stepping down as he seeks to calm anger and stave off the street protests which have gripped Egypt and Tunisia.
Yemen is viewed as the second most important battleground by the US after Afghanistan and the decision by Ali Abdullah Saleh to leave office after three decades augurs uncertain times for the campaign against al-Qa'ida. Ahead of a planned "day of rage'", Mr Saleh asked the opposition parties to form a coalition government after declaring that he will not seek re-election when his current term ends in two years' time. He insisted that his son Ahmed, thought to be his political heir, will also be out of the running.
Yemen, with its combustible mix of Islamist militancy, tribal warfare and endemic poverty, was considered a prime candidate to be the next "domino" after the uprisings in Tunisia and Egypt, and President Saleh's move was described by his supporters as a statesmanlike attempt to avert widespread bloodshed.
The country's biggest opposition group, the Islamic Islah, welcomed Mr Saleh's departure but has refused to cancel the protest march.