Nominations for Afghanistan's presidential elections were set to close on Sunday, with deals being cut among former warlords, veteran politicians and tribal leaders in a last-minute frenzy of political manoeuvring.
At least three major contenders waited until the final day of nominations to declare whether they would run in the April 5 contest to succeed President Hamid Karzai, who has ruled the country since the fall of the Taliban in 2001.
Ashraf Ghani, a former finance minister, will register on Sunday, his officials said, while Zalmai Rassoul, the foreign minister, and Qayum Karzai, the president's brother, are also seen as possible late entries in the wide-open race.
The two big-name candidates to have already declared are Abdullah Abdullah, the runner-up to 2009, and Abdul Rab Rasoul Sayyaf, a former warlord with previous links to Al-Qaeda.
Karzai, who retained power in 2009 amid allegations of massive fraud, has vowed not to endorse any candidate -- but many of his supporters are looking for covert signals to reveal his favoured candidate.
International donors, led by the US, see the elections as the key test of progress after 12 years of military intervention and billions of dollars of aid to try to develop Afghanistan since the end of the austere Taliban regime.
Jan Kubis, head of the UN mission in Kabul, said on Thursday that holding a credible election on time was the "best argument" Afghanistan could make for securing further international support.
The election will come as NATO coalition troops pull out by the end of next year, with 87,000 soldiers -- 57,000 of them from the US -- currently deployed to fight Taliban insurgents and train up the local army and police.
Four NATO troops were killed fighting in south Afghanistan on Saturday, underlining the continuing cost of the war. Their nationalities were not immediately released.
The size of the final election field remained uncertain, but Karzai has called for just two or three runners to contest on polling day to avoid the chaos of the 2009 vote when 40 names appeared on the ballot paper.
Peace talks with the Taliban and a deal to allow some US troops to remain in the country after 2014 are likely to be two hot topics of debate as Afghanistan prepares for its first ever democratic transfer of power.
Early attempts to start a peace process floundered in June, but Washington and other foreign powers all back a negotiated end to the long war.
The Taliban, who targeted previous elections, have refused to open talks with the Kabul government, dismissing it as a puppet of the United States.
After nominations close at 4:00 pm (1130 GMT), the Independent Election Commission will verify the legibility of each candidates and their two vice-presidential picks.
A final list of runners will be announced on November 16, with official campaigning beginning in February.