Iraq's prime minister has appealed to neighboring states to co-operate in tackling the insurgency which has left tens of thousands dead since 2003.

Addressing an international meeting in Baghdad, he did not name any particular country. But the US accuses both Iran and Syria of stoking the violence.

The talks bring envoys from all three together for the first time in years.

Soon after they started, at least two mortar shells landed near the venue but injured no-one, a witness said.

Earlier at least five people were killed by a car bomb in the Sadr City area of east Baghdad.

Those attending the one-day conference on ways to restore stability include envoys from other members of the UN Security Council, the Arab League, the Gulf Cooperation Council as well as other states bordering Iraq.

Observers say it is seen as an attempt to break the ice, and the beginning of a process. It is hoped the next step will be a meeting of foreign ministers in April.

'In the front line'

The BBC's Jim Muir in Baghdad says that for Iraq the meeting is an important opportunity to bring together neighbors and other powers who have often seemed to be using the country as a proxy battlefield for their own struggles.

A key focus will be reducing violence stemming from Iraq's Sunni-Shia divide.

In his opening address, Iraqi Prime Minister Nouri Maliki called terrorism "an international epidemic" for which the people of Iraq were paying the price.

"Iraq is the first front line in facing this terrorism - which needs a lot of international co-operation to confront it - especially the neighboring countries in particular to support us in this great war."

He added that apart from threatening Iraq, the battle could spill over to all countries of the region.

"Brothers, facing terrorism means that we must stop any form of financial or media support and religious cover (for terrorist acts), as well as stopping logistical support, the flow of weapons and men who transform themselves into bombs to kill our children, women and old men, and who are destroying our mosques and churches."