**Gordon Brown is due to mount a robust defence of Britain’s military policy in Afghanistan by warning al-Qaeda is the biggest threat to UK national security.**He will say this year’s fighting has had the greatest impact against al-Qaeda of any 12-month period since the war in Afghanistan began in 2001.
The prime minister is due to speak at the Lord Mayor’s banquet in the City of London on Monday evening.
Sunday saw the death of the 96th UK serviceman to be killed this year.
In his annual Guildhall foreign policy speech, Mr Brown will warn that al-Qaeda continues to recruit and train and could return to Afghanistan if international forces pulled out.
‘On-going threat’
He will say there are “several hundred” foreign fighters still based in the tribal areas of northern Pakistan, attending training camps to learn bomb-making and weapons skills.
The group continues to operate “an extensive recruitment network across Africa, the Middle East, western Europe and in the UK”, he will warn.
“We are in Afghanistan because we judge that, if the Taliban regained power, al-Qaeda and other terrorist groups would once more have an environment in which they could operate,” he will argue.
“I say our foreign policy must be both patriotic and internationalist”
Gordon Brown
"We are there because action in Afghanistan is not an alternative to action in Pakistan, but an inseparable support to it.
"At every point in our history where we have looked outwards, we have become stronger.
“And that is why I say our foreign policy must be both patriotic and internationalist: a foreign policy that recognises and exploits Britain’s unique strengths, and defends Britain’s national interests strongly - not by retreating into isolation, but by advancing in international co-operation”.
In recent weeks, the prime minister has attempted to bolster public support for British forces in Afghanistan with a radio interview, a speech to military leaders and an address to the Commons.
Yet a poll published on Sunday suggested 71% of Britons want to see British troops withdrawn from Afghanistan within a year.