Two men considered front-runners in Afghanistan's presidential election were the last to file their nominations, beating a deadline for candidates by only hours.

By the closure of nominations on Sunday, about 20 presidential candidates had registered for the April 5 elections, the first independent vote organised by Afghanistan without direct foreign assistance.

In chaotic scenes outside the Independent Election Commission in Kabul, Qayum Karzai, the older brother of incumbent Hamid Karzai, submitted his papers with only moments to spare with police barring his supporters due to overcrowding.

Prominent Candidates Abdullah Abdullah Former foreign minister and runner-up to Hamid Karzai in 2009.

Ashraf Ghani Pashtun former finance minister running with vice presidential candidates Abdul Rashid Dostum, a former Uzbek warlord and Sarwar Danish, a former justice minister.

Abdul Rab Rasoul Sayyaf Pashtun former warlord. Running mates are Ismail Khan, a former regional commander from Herat, and Abdul Wahab Erfan, an ethnic Uzbek who served in the upper house of parliament.

Qayum Karzai Hamid Karzai's brother who is running with Wahidullah Shahrani, an Uzbek, and Abrahim Qasimi, who was a Hazara member of parliament.

He was the last of the major candidates to register, arriving hours after another leading candidate, Ashraf Ghani, had filed his papers.

Election nominees are a mix of Afghanistan's past and current power players, warlords with a tainted history, technocrats and some political outsiders.

Abdullah Abdullah, a former foreign minister and runner-up to Karzai in the 2009 elections, is also among the early favourites.

Karzai is not entitled to run for a third consecutive term. He is, however, expected to back Rasoul over his brother.

To run, candidates must have at least 100,000 signatures backing their nomination, and their candidacy will be reviewed by the Independent Electoral Commission before final approval on November 11.

Candidates were also required to declare two vice-presidents.

All the candidates have tried to shape tickets that attempt to unify an

ethnically fractious political scene marked by patronage and alliances among

the elite, which can marshal votes among the country's various ethnic groups.

The population of 31 million is roughly 42 percent Pashtun, 27 percent Tajik, nine percent Hazara, and nine percent Uzbek along with other, smaller factions.

Billions of dollars in funds pledged to Afghanistan are tied to the government holding transparent and credible elections, a challenge in a country rife with patronage and corruption and a resilient Taliban insurgency.

The Taliban has told Afghans not to vote and said it does not recognise the election process.