"The army says it has secured large areas and that it has hit the militant movement very strongly, but the fact that we are still escorted by helicopter gunships ... indicates that there is still a fear of ongoing action," he reported.

Humanitarian concerns

The military also claims to have cleared the Taliban from mountain hideouts in Peochar.

In depth


 Video: The fight for Mingora
 Riz Khan: Obama's 'AfPak' strategy
 Riz Khan: The battle for the soul of Pakistan
 Q&A: The struggle for Swat
 Your views: Crisis in Swat
 The fight for northwest Pakistan
Talking to the Taliban
Pakistan's war
 Pakistan diary

But the army's advance has come at a cost.

An estimated 1.9 million people have fled the fighting in Swat and its neighbouring districts since the army launched its offensive last month.

More than 160,000 are staying in camps just south of the battle zone, while the rest have been taken in by relatives.

The United Nations appealed on Friday for $543m to ease the "incredible suffering" of the nearly two million refugees.

The world body said the money was urgently needed to fund some 165 projects drawn up by UN agencies and aid groups to assist civilians.

"The scale of this displacement is extraordinary in terms of size and speed and has caused incredible suffering," Martin Mogwanja, the acting UN humanitarian co-ordinator in Pakistan, said in a statement.

"We are calling for generous support from the international community."

US pressure

The Pakistani effort to halt the Taliban follows urging from the US, which is itself battling Taliban fighters in neighbouring Afghanistan.

Some have expressed concern that a planned US troop build-up in Afghanistan could further destabilise Pakistan.

But Admiral Mike Mullen, the US joint chiefs of staff chairman, said that efforts were under way to avoid that.

He told the senate foreign relations committee in Washington that he believed the upcoming increase of 21,000 US troops in Afghanistan was "about right" to tackle the Taliban there.