File photo of Presidential rivals Abdullah Abdullah (L) and Ashraf Ghani (R) in Kabul. (Reuters)
Afghanistan's presidential rivals signed a power-sharing deal on Sunday, ending a prolonged stand-off over disputed election results at a pivotal moment in the war-weary nation's history.
Ashraf Ghani, who is set to become president when official results are finally released, embraced Abdullah Abdullah briefly at a low-key and solemn ceremony in the presidential palace that lasted less than 10 minutes.
The deal broke a three-month deadlock over allegations of massive electoral fraud that plunged Afghanistan into crisis as US-led troops end their 13-year war against the Taliban.
Both Mr Ghani and Mr Abdullah claimed to have won the vote, but Mr Ghani is widely reported to have come out ahead after a UN-supervised audit of all eight million ballot papers.
Under Sunday's deal Mr Abdullah will nominate his choice for the new post of "chief executive officer" (CEO), which will be similar to prime minister setting up a tricky balance of power as Afghanistan enters a new era.
"I'm happy that our brothers Dr. Ashraf Ghani and Dr. Abdullah struck an Afghani deal for the sake of goodness and prosperity of the country," outgoing President Hamid Karzai said in a short speech after the signing.
"I hope with their efforts this country gets long-lasting peace."
Neither candidate spoke at the ceremony, and it remained uncertain when they would address the nation, when the agreement would be published or when the official election results would be announced.
Under the constitution the president wields almost total control, and the new government structure will face a major test as the security and economic outlook worsens.
The vote count has been plagued by months of setbacks amid allegations of massive fraud, emboldening the Taliban insurgents and further weakening the aid-dependent economy.
As tensions rose in Kabul, the United Nations and United States pushed hard for a "national unity government" to avoid a return to the ethnic divisions of the 1990s civil war.
Will the deal stick?
The future of Afghanistan's relationship with the US-led NATO alliance also hangs in the balance after Mr Karzai refused to sign a bilateral security pact with Washington to ensure a continued foreign military presence after this year.
The White House welcomed the deal, which it said "helps bring closure to Afghanistan's political crisis".
"We look forward to resolution of the electoral process with the announcement of the election outcome... and the conclusion of the Bilateral Security Agreement," it added in a statement.
A ruling coalition between the opposing camps is likely to be uneasy after a bitter election that revived some of the ethnic rivalries of the civil war which ended with the Taliban taking power in Kabul in 1996.
Mr Abdullah, a former anti-Taliban resistance fighter, draws his support from Tajiks and other northern ethnic groups. Mr Ghani, an ex-World Bank economist, is backed by Pashtun tribes of the south and east.
According to a draft of the unity government document seen by AFP, the CEO role will become "executive prime minister" in two years' time a major change to the way Afghanistan has been ruled since 2001.
Mr Abdullah could take up the prime minister role, but is thought likely instead to nominate an ally to the key job.
Dividing up other official posts could also create friction after the long and mercurial reign of Mr Karzai, who built up a network of patronage through his appointment of officials at all levels of government.
After the June run-off election was engulfed in fraud allegations, the US brokered a deal in which the two candidates agreed to abide by the outcome of the audit and then form a national unity government.
But Mr Abdullah later abandoned the audit, saying it was failing to clean out fraud. He won April's first round, only to see Mr Ghani come from well behind and win in June.
The new administration will have to stabilise the economy as international aid falls, and deal with worsening unrest nationwide.
Efforts to open a peace process with the Taliban failed under Mr Karzai and may be revived.