Representatives from about 70 countries and organizations will meet in Tokyo on July 8 to pledge funding and support to Afghanistan after foreign troops leave at the end of 2014.
Afghan President Hamid Karzai has said he will ask for $4 billion annually for the first three years after the withdrawal.
Donor nations, however, have said they want more guarantees that their taxpayers' money will not be lost to corruption and mismanagement.
Rights group Amnesty International says donors need confirmation that the aid is directed "to human rights improvements that make a difference to Afghan lives."
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 nation in the world.
Based on reporting by AP and RFE/RL