Terror resolve undiminished - Fox
The choice of a new leader for militant group al-Qaeda is an academic issue, Defence Secretary Liam Fox has said during a visit to Afghanistan.
Dr Fox said whoever was heading the group, the resolve to rid the world of violent extremism was undiminished.
Ayman al-Zawahiri has been appointed as the head of the organisation following the death of Osama Bin Laden.
Dr Fox also said the progress Nato forces were making in Afghanistan was good but "far from irreversible".
Speaking to the BBC Persian Service in the Afghan capital, Kabul, Dr Fox said: "Whoever happens to be heading al-Qaeda is in many ways an academic issue, because our resolve is undiminished.
"The need to rid ourselves of violent extremism, under whatever guise, is undiminished, and we will continue to deploy whatever assets are required to deal with that problem in an undiminished way.
"So for us the problem is the existence of the threat... and we'll be just as determined to deal with it, whoever is nominally in charge of the organisation."
Dr Fox was speaking at the end of a 24-hour visit to UK troops serving in Afghanistan.
Speaking about the progress against the Taliban he said: "There is no doubt that we are making progress. The security situation is improving. There are some hints that the Taliban may be losing the battle of hearts and minds but there is a great deal to be done and it is far from irreversible."
He also hinted there would be no early withdrawal of British troops.
"How quickly we can draw our forces down is dependent on the security situation on the ground, what role our allies are playing and, of course, what the state of the Afghan national forces will be," Dr Fox said.
"None of us want to have our troops in harm's way any longer than possible. But we also have to remember that the point of the mission is to succeed and not leave as early as possible."