VLADIVOSTOK, Russia — In a report to Congress on Friday, Secretary of State Hillary Rodham Clinton formally designated the militant Haqqani network — responsible for some of the deadliest attacks against US troops in Afghanistan — as a terrorist organization, two days before a congressional deadline.

Clinton signed the order in Brunei before departing to Vladivostok for the annual Asia Pacific Economic Conference, and State Department officials began notifying senior lawmakers. She issued the report after a last round of internal debate that took place in Washington on Thursday hours before President Obama spoke at the Democratic National Convention.

The administration’s special envoy, Marc Grossman,was expected to formally inform Pakistan’s leaders Friday.

The decision is the culmination of nearly two years of spirited debate that reached a peak in the past month under the pressure of Sunday’s reporting deadline.

Several State Department and military officials had argued that designating the organization would help strangle the group’s fund-raising activities in countries like Saudi Arabia and the United Arab Emirates and pressure Pakistan to open a long-expected military offensive against the militants.

Many other senior officials, including several in the White House, expressed deep reservations that blacklisting the group could further damage badly frayed relations with Pakistan, undercut peace talks with the Taliban, and possibly jeopardize the fate of Sergeant Bowe Bergdahl, the only US soldier known to be held by the militants.