The sending a senior diplomat to secure Pakistan's support against the Haqqani insurgent network and to persuade Afghanistan to continue three-way talks with the U.S. and Pakistan on counterterrorism and economic development.

Marc Grossman, U.S. special envoy to Afghanistan and Pakistan, will leave Friday for meetings in Kabul and Islamabad.

State Department spokeswoman Victoria Nuland said Grossman would also visit neighboring countries.

She said Grossman would speak with Pakistan about how to "tackle the Haqqani network."

The group attacked the U.S. embassy in Kabul this month and Joint Chiefs Chairman Adm. Mike Mullen has called it "a veritable arm" of Pakistan's intelligence agency.

Nuland also acknowledged Afghan concerns about U.S.-Pakistani-Afghan talks. She said Grossman would speak to both parties about the value of continuing the discussions.