A United Nations official says more than 140,000 Iraqis have fled parts of Anbar province over clashes between security forces and al-Qaida militants.

The spokesman for the U.N. High Commissioner for Refugees, Peter Kessler, described it as "the largest" displacement witnessed in the country since the sectarian violence of 2006-2008.

He added that more than 65,000 people fled the conflict in the cities of Ramadi and Fallujah just in the past week alone.

Since late December, members of Iraq's al-Qaida branch — known as the Islamic State of Iraq and the Levant — have taken over parts of Ramadi, the capital of the largely Sunni province of Anbar. They also control the center of the nearby city of Fallujah.