CBS' Steve Kroft interviews U.S. President Barack Obama for CBS' "60 Minutes" program, in the Oval Office in Washington.

NEW YORK: Stressing on the need of establishing peace and a secure environment in Pakistan and Afghanistan, US President Barack Obama has said that dismantling the terror network flourishing in the region is the “singular focus” of his administration.

In an extensive interview with the ABC, Obama said rooting out the militant base in the Pak-Afghan region was the ‘central concern’ of the US and also the main objective of the Afghan strategy.

“We’ve got to work both in Afghanistan and in Pakistan to create an environment in which these extremist organisations are further and further isolated,” Obama said.

Defending his decision to send in more troops to Afghanistan, the US President said there are people hiding in the region who had killed over 3000 Americans on September 11, 2001, adding that the extremists would not be allowed to repeat the tragedy at any cost.

“And those people are still out there, still plotting to kill Americans. So the reason the American troops are there, first and foremost, is because we’ve got to make sure that something like that doesn’t happen again,” Obama said.

“We are going after Al Qaeda to dismantle and destroy them. I said at the beginning of my Afghan strategy, that was our central concern. And that remains our singular focus,” he added.

Describing Afghan President Hamid Karzai as a ‘critical partner; in the fight against Al-Qaeda and the Taliban, Obama underlined that Karzai has a daunting task ahead of him of building a stable civilian country.

“Now, President Karzai, I think, is going to be a critical partner in this effort, because if we are just succeeding on the military side, but not succeeding on the civilian side, then you’re going to continue to have instability in the region,” The Dawn quoted Obama, as saying.