Prime Minister Maliki said the pull-out was according to schedule and that both sides were obliged to carry it out.

But, speaking Saturday, he noted that any chance of extending the mission collapsed over the issue of immunity.

The prime minister said Iraqi political factions rejected the notion of US forces in Iraq working outside Iraqi laws.  That ban on immunity appeared to extend to any American military personnel sent to Iraq after this year to provide training.

The US had been adamant that its forces would have immunity, a protection provided by other countries where American troops are stationed.

Some in Iraq say they worry about continued fragile security, while many others say that nearly nine years after the US-led invasion, it's past time the Americans go home.

VOA