Clinton said the Haqqani Network meets the statutory criteria for such status under the Terrorist Designation Act and is a specially designated global terrorist entity as defined by Executive Order 13224.
The designation means Haqqani's U.S. assets will be frozen and the administration will work with other countries to freeze the network's foreign assets.
"By way of background, we've long been aware of the Haqqani Network's intent to cause instability in Afghanistan and attack and kill U.S. civilians and military service members," a senior administration official said in a background briefing.
A second administration official said military efforts against Haqqani will continue.
The action ends two years of heated debate within the upper ranks of the U.S. government.
Officials within the State Department and Pentagon had argued for the designation, saying it would greatly reduce the flow of funds from nations such as Saudi Arabia and the United Arab Emirates and pressure Pakistan to take action against the group.
Other senior officials, including some in the White House, disagreed. They maintained such a step could further damage relations with Pakistan, stall peace talks with the Taliban and jeopardize the fate of an American soldier known to be held by militants.
Pakistan was informed of Clinton's decision in advance of the announcement and "senior civilian and military leadership in Pakistan ... did not express concern about this designation and are -- remain committed to battling extremism in Pakistan," the first senior administration official said.
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