The Electoral Complaints Commission (ECC) has published the results of its investigation into fraud in the Afghan presidential election. The BBC understands the findings indicate that Hamid Karzai did not gain enough votes to win the election outright. According to poll rules, there should now be a second round.
BBC News examines possible scenarios.
AFGHANISTAN PREPARES FOR A RUN-OFF
If no candidate secures more than 50% of ballots then the constitution states there has to be a second round run-off between the two with the most votes.
This has to be held within two weeks of the announcement of a result.
But the rapid onset of winter from early November will make matters difficult, with parts of the country almost inaccessible.
There is a fear that the journey to a local polling station in the depths of winter will simply be too gruelling for many Afghans.
In addition, the authorities will have to once again mobilise election officials, polling stations, polling cards, security and organise the collection of ballot boxes and counting.
Decisions about the location of polling stations and the staff they hire to man them will also have to be made to prevent repeating mistakes made in the first round.
The election itself took months to plan. The run-off would have a matter of weeks. But authorities are reported to have already printed ballot papers.
Many analysts say Mr Karzai, a Pashtun from the country's largest ethnic group, would probably still win any second round.
Correspondents say there is no guarantee, however, that the authorities could prevent the security breaches and corruption that marred the first round.
But delaying a vote until the spring would leave Afghanistan in political limbo at a time when major Western powers are deciding whether to send more troops or not - leaving the way open for militants to make their mark.
Many analysts suggest a substantial delay is highly unlikely.
ECC FINDINGS ARE DISPUTED
It is also possible that Afghanistan's election commission or one of the main challengers will not accept the findings of the fraud investigation.
AFGHAN FRAUD ALLEGATIONS
30 Sep: UN recalls envoy Peter Galbraith following row over the vote recount process
15 Sep: ECC chief says 10% of votes need to be recounted
8 Sep: Poll complaints body orders some recounts nationwide
8 Sep: IEC says votes from 600 polling stations "quarantined"
3 Sep: Claims 30,000 fraudulent votes cast for Karzai in Kandahar
30 Aug: 2,000 fraud allegations are probed; 600 deemed serious
20 Aug: Election day and claims 80,000 ballots were filled out fraudulently for Karzai in Ghazni
18 Aug: Ballot cards sold openly and voter bribes offered
They could decide to mount a legal challenge to the ECC's findings.
The legal position is not clear. As things stand the election commission is bound to accept the ECC's findings and invalidate results accordingly.
However, recent media reports suggest Hamid Karzai may not accept the results and could launch a Supreme Court challenge to the ECC's findings - which would further postpone a final result.
Mr Karzai led preliminary results with about 55% of the vote, considerably ahead of former foreign minister Dr Adbdullah Abdullah, who was on 28%.
It is not clear on what basis any challenges to the ECC's findings would be made. But some analysts say the methodology it used could be disputed.
An Afghan member of the five-member ECC panel recently resigned saying that Afghans were not involved in decision-making on the panel. Dr Abdullah's team accused Hamid Karzai of being behind the resignation.
A UNITY GOVERNMENT BRINGS OPPONENTS TOGETHER
Another option which has been suggested is that the main challengers form a power-sharing government.
There has been intensive diplomacy in recent days, aimed at ensuring the UN-backed election process is respected.
Some observers say diplomats have also been pushing the protagonists to reach a deal that would avoid more voting.
Mr Karzai has been insisting that he be declared the winner and then he will include members of Dr Abdullah's team in his cabinet.
Dr Abdullah at first ruled out negotiations but in recent days he appears to have softened his stance.
In comments to the press on Wednesday, Dr Abdullah said: "Once results are announced, I would be open to dialogue."
And in an interview on US television last week, Mr Karzai said that for the past seven years, he had been known as "a man who brings inclusiveness".
"The unity of [the] Afghan people is paramount here and we will continue to strive for that," he said.
TRADITIONAL LOYA JIRGA TO RESTORE LEGITIMACY
Some analysts have suggested that one possible course of action is that a loya jirga - a traditional tribal gathering of senior politicians and tribal leaders - meets to broker a solution to the impasse at some point in the political process.
Many ballot boxes were quarantined after the elections
This could happen at any time, whether or not there is a second round after fraudulent ballots are discarded.
One possible scenario is that a run-off is called, Mr Karzai wins a second round, but he still convenes a loya jirga at the end of it all to suggest solutions which could restore legitimacy and credibility to a bedevilled process.