International donors meeting in Tokyo have pledged some $16 billion in development aid to Afghanistan until 2015.
Donors states also vowed to maintain their aid to Kabul through to 2017, at or near levels of the past decade.
The one-day conference in Tokyo, attended by representatives of over 70 countries and international organizations, was aimed at filling the gap between what Kabul gets from its barely functioning economy and what it needs to develop into a stable country.
Kabul generates only about a third of the $6 billion it spends each year, not counting security costs, and is heavily dependent on foreign aid.
Opening the conference, UN Secretary-General Ban Ki-moon said failure to support Afghan civil society once international forces leave in 2014 could put at risk the sacrifices in blood and treasure over the last decade.
Ban said Afghanistan was at a crossroads.
"We are at the critical moment of Afghanistan's history in transition from reliance on the aid that has enabled the country's institutions to take root to a normalized relationship of a sovereign functioning Afghanistan with its people and with it's international partners," Ban told the opening session.
"This is a vital conference for Afghanistan," Japanese Foreign Minister Koichiro Gemba said. "It can create a viable path for sustainable development beyond 2015."
Kabul has expressed fears that once foreign troops pull out by 2014, international aid will drop.
"Our expectation from the Tokyo conference is that the international community will keep its commitment during the [18-month] transition period and also during the transformation decade," Amin Fatemi, Afghanistan's ambassador to Japan, told RFE/RL's Radio Free Afghanistan.
"We hope the international community will be serious and implement its commitments and accept Afghanistan's economic, development, and growth strategies during the conference."
The pledges came as the Afghan government agreed to new conditions to improve governance and combat endemic corruption.
Afghan presidential spokesman Email Faizi, speaking to Radio Free Afghanistan on July 8, said Kabul had a plan to make sure international aid is spent properly and not mismanaged.
"The international community is not donating this amount to Afghanistan easily. In return, they ask for some efforts. Fighting against corruption, good governance, and strengthening governmental institutions are some of the points that the international community stresses," Faizi said.
"The Afghan government also has a special plan for the coming two years to focus more on strengthening it's institutions, fighting against corruption, and [working for] better governance."
Afghanistan has received nearly $60 billion in aid since 2002, but corruption remains rampant in the country.
Transparency International last year said Afghanistan was the second-most corrupt country in the world.
Karzai addressed such concerns in his opening remarks.
"I recognize, ladies and gentlemen, that the success of our partnership will depend on our mutual ability to be accountable and to prove our practices so that the hard-earned money of your taxpayers are utilized most effectively and transparently," Karzai said.
At the end of the conference in Japan, donor states agreed to hold a follow-up conference in the United Kingdom in 2014.
Meanwhile, U.S. Secretary of State Hillary Clinton said she was confident that the pledges by the international community would lead Afghanistan toward a path of "self-sufficiency."
"I believe that we have really made a good commitment to putting Afghanistan on a path to economic self-sufficiency," Clinton said. "As Afghan capacity and revenues increase, our contributions can decline."
In an unannounced visit to Kabul a day earlier, Clinton announced that Washington had designated Afghanistan its newest "major non-NATO ally," becoming the 15th country to secure the status.
Afghanistan's neighbor Pakistan was the last nation to gain the designation in 2004.
The declaration was part of a strategic partnership agreement signed by Presidents Barack Obama and Karzai in Kabul at the beginning of May.
Analysts say the move will facilitate defense cooperation between the two countries and make it easier for Afghanistan to acquire U.S. defense materiel.
With reporting by AP, dpa, AFP, and Reuters