Border clashes with Haqqani fighters and coalition forces have produced some of the heaviest fighting since the Obama administration surged more than 20,000 U.S. troops into the southern part of the country in 2009.
Most recently, members of the Haqqani Network launched a cross-border attack against a hotel outside of Kabul last week.
Afghan National Security Forces and Haqqani gunmen exchanged heavy fire during the 12-hour standoff, which ended with nearly 20 Afghan civilians dead.
However, a number of top Pentagon officials including Defense Secretary Leon Panetta have accused Islamabad of providing safe haven and support to Haqqani fighters and other militant Islamic groups inside its borders.
Top lawmakers on Capitol Hill have demanded the State Department place the Haqqani Network on its list of officially-recognized terrorist groups.
Sen. Dianne Feinstein (D-Calif.), head of the Senate Select Committee on Intelligence, and House Permanent Select Committee on Intelligence Chairman Mike Rogers (R-Mich.) said last month the Haqqani group's actions along the border have strengthened Taliban control inside Afghanistan.
As a result, the Pentagon and CIA have ramped up aerial drone strikes against suspected terror targets inside Pakistan's borders. American drones reportedly killed four militants during an airstrike in North Waziristan on Tuesday.
Pakistan continues to demand outright cancellation of all American-led unmanned airstrikes inside the country.