"I view it (terrorist safe havens inside Pakistan) as a serious problem," Gen John "Mick" Nicholson told members of the Senate Armed Services Committee during his confirmation hearing (Read the full text of his confirmation hearing HERE).
If confirmed by the Senate, he would replace Gen John Campbell as Commander of the US and NATO forces in Afghanistan at a time when serious concerns have been raised about the security situation in Afghanistan, where Taliban terrorists have caused large numbers of casualties and Islamic State affiliates have made some inroads.
"One of the biggest problems has been the sanctuary, particularly for the Haqqani Network, particularly the involvement of the ISI in Pakistan, which in many cases have been supporting the Haqqani Network. Have you seen any progress in this whole problem?" Senator John McCain, chairman of the Senate Armed Services Committee, asked Gen Nicholson.
In response, Gen Nicholson said continued presence of the terrorist safe haven has been a major problem.
"This has been one of the principal challenges. It's a sanctuary that our enemies, in particular the Haqqani Network, have enjoyed inside Pakistan," he said.
"I note that the Pakistanis have also suffered significant casualties in the tens of thousands in terms of their security forces and their civilians," he noted.
However, the US is not satisfied that there's adequate pressure put on the Haqqanis, he told the Senators.
The recent operations in northern Waziristan have helped, as well as stationing of additional soldiers in tribal areas.
"Some of this has pushed some fighters into Afghanistan, which has contributed to some of the issues there," he said.
"So, it's a mixed story, and it's one that requires continuous engagement by the Pakistan military. And then, increasingly, we want to encourage the Afghans and the Pakistan military forces to work more closely together against their common enemies," Nicholson said.
Earlier, in a written response to questions, Nicholson asked Pakistan to take persistent action against the Taliban, particularly the Haqqani Network.
"Pakistan's pressure on the Taliban combined with its support to the reconciliation process are mutually reinforcing," he added.
Haqqani network, which is linked to Al Qaeda has also been blamed for several deadly attacks against Western and Indian interests in Afghanistan, including the 2008 bombing of the Indian mission in Kabul.
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