US-led forces patrol the Afghan side of the border with Pakistan

Washington has pinpointed the frontier areas of Pakistan and Afghanistan as the most pressing central point in which to win the war on terror.

Michael Chertoff, the US secretary for homeland security, told the BBC that successes against al-Qaeda should not lead to a weakening of resolve.

He warned that militants in Pakistan were training recruits who could mix inconspicuously in Western society.

He questioned whether Pakistan’s rulers had the right strategy to respond.

Mr Chertoff said the US had succeeded in pushing back al-Qaeda in Iraq and argued that Muslims in Iraq were now reacting against indiscriminate militant violence.

But he warned that: “If we lose our resolution, we could find ourselves actually losing ground.”

‘Freely and inconspicuously’

While the threat from al-Qaeda remained global, he said, there was no specific intelligence now of an imminent attack.

Michael Chertoff has led the homeland security department since 2005

He did not want people to be over-anxious but he warned that al-Qaeda and associated groups were still intent on carrying out attacks on the US, Europe and elsewhere.

“[Al-Qaeda] are using their platform in the frontier areas of Pakistan to train operatives, including operatives who don’t fit what perhaps the public believes is the normal profile of a terrorist,” he said, during a visit to the UK.

“They are looking for people who can operate freely and inconspicuously in Western society.”

He said the “jury was still out” on the strategy of Pakistan’s new democratic government to combat the militants.

Addressing Oxford University students during his visit, Mr Chertoff said extremists had “hijacked the language of Islam to mask an ideology that in some respects has more in common with the fascist organisations of the 1930s”.

You can hear the interview on BBC Radio 4’s The World This Weekend programme at 1300 BST on Sunday 1 June.