The U.S. has moved to designate the Pakistan-based Haqqani network as a terrorist organization, a decision that could pave the way for tough financial sanctions against the militant group.

A senior State Department official says Secretary of State Hillary Clinton signed a report to Congress Friday that says the group meets the criteria for a terrorist designation.

The Haqqani network has been blamed for attacks on U.S. troops in Afghanistan and assaults on the U.S. Embassy in Kabul, last year.

The group, which is reportedly based in Pakistan's North Waziristan tribal area, is believed to have close ties with elements of Pakistani intelligence. Pakistani officials have rejected the allegations.

The French News Agency quotes a senior Pakistani security official as saying a terrorism designation would negatively impact future U.S. relations with Pakistan.

Also, some U.S. officials have expressed concern that placing the network on a blacklist could further damage already fragile relations with Pakistan and slow efforts to negotiate a political settlement to the Afghan war by undercutting talks with the Taliban.

Afghan Interior Ministry spokesman Sediq Sediqqi on Friday welcomed any move by the United States to target the Haqqani network.

The U.S. has been pressing Pakistan to launch a military offensive in North Waziristan, but the Pakistani army has said its forces are stretched too thin to target militants in the tribal agency.

U.S. and Pakistani officials confirmed last week that a drone strike killed the day-to-day operations commander of the Haqqani network, Badruddin Haqqani.