The United States and other nations vowed Monday to keep supporting Afghanistan after most foreign forces leave the country in 2014, as the nation faces an enduring Taliban-led insurgency and possible financial collapse.

"The United States is prepared to stand with the Afghan people for the long haul," U.S. Secretary of State Hillary Rodham Clinton told a global conference on Afghanistan's future that was overshadowed by the absence of key regional player Pakistan. The international community has "much to lose if the country again becomes a source of terrorism and instability," she added.

Clinton stressed that in return for continued support the Afghans must live up to their commitments "on taking difficult decisions to embrace reform, lead in their own defense and strengthen an inclusive democracy rooved in the rule of law."

About 100 countries and international organizations are represented among the 1,000 conference delegates, including some 60 foreign ministers.

"Together we have spent blood and treasure in fighting terrorism," Afghan President Hamid Karzai said. "Your continued solidarity, your commitment and support will be crucial so that we can consolidate our gains and continue to address the challenges that remain. We will need your steadfast support for at least another decade."

"No one is more interested than the United States in getting to the bottom of what happened in the border incident," Clinton said with an edge in her voice. She has called the deaths tragic and pledged a thorough investigation, but Pakistan rebuffed her entreaties, as recently as Saturday, to reconsider and attend the conference.