Islamabad, Nov 18 : John Negroponte, the US Deputy Secretary of State, has said that the United States is concerned at Islamic militancy in Pakistan's North West Frontier Province (NWFP), and believes that it will take some time for Islamabad to overcome the unrest.

Negroponte admitted that Pakistan faced "challenges" in the scenic Swat Valley of the NWFP, where pro-Taliban militants loyal to a radical cleric have made sweeping gains over the past few months.

"It is yet another reason to be concerned about the situation in Pakistan, " he told reporters here.

"The situation in Swat is a reminder of the fact that there are issues to deal with regarding violent extremists in this country. The Pakistan Government is undertaking major efforts at the moment to deal with the situation in Swat and I suspect it will be doing so for a while to come, " Negroponte said.

Pro-Taliban militants in the semi-autonomous tribal belt bordering Afghanistan and the militancy in Swat have embarrassed Musharraf's government, who cited the danger of extremist as one of the reasons for imposing emergency rule.

On Saturday, Pakistan's Director General Of Military Operations, Major General Ahmed Shuja Pasha, promised a major operation "any time from now" to clear militants from Swat.

Major General Pasha said that five days of clashes which have left reportedly 100 insurgents dead in the past week was only a prelude to the offensive.

He said he hoped the mountainous area could be reopened to tourists by the end of December, The News reported. (ANI)