Delegates to Afghanistan's loya jirga, or grand assembly, are expected to vote Monday on the country's future system of government.
News reports say Afghan President Hamid Karzai appears to have persuaded most delegates that the president should retain sweeping powers set forth in the government's draft of the country's new constitution.
Some Afghan warlords reportedly had been insisting on a parliamentary government headed by a prime minister to balance the president's power.
The 502 delegates to the loyal jirga were supposed to vote on the amended constitution on Sunday, but the final vote was postponed a day because printed versions of the charter were not available.
Adoption of the constitution will pave the way for democratic elections next June.
Over the past two weeks, the delegates, who include 100 women, also have been debating a number of other issues, including the role of Islam, human rights and equal rights for women.