British and U.S. forces are poised to take the town of Marjah, the last major bastion of Taliban control in the province, in what will be one of the biggest operations of the eight-year-old war.

Brigadier James Cowan told that the number of civilians leaving their homes were exaggerated by some of the media.

Around one hundred families have fled Marjah and surrounding areas, seeking refuge in Lashkar Gah over the last week, the provincial governor´s spokesman Dawood Ahmadi said on Sunday. Afghan families average around six members. Some of those had fled from areas around Marjah where British "shaping" operations have been taking place.

British forces and U.S. Marines are expected to lead a major offensive on central Helmand towns, an operation they codenamed as Moshtarak which means "together" in the local language.

The military strategy calls for taking control of districts in opium-rich Helmand and neighbouring Kandahar provinces from fighters who seized them over the last several years.

Commanders have flagged their intention to seize Marjah for months in the hope of persuading less-committed Taliban fighters to flee or lay down arms rather than stand and fight.