AFP/Kabul
Afghanistan's two rival presidential candidates 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.
The final vote count is also scheduled for release, after being delayed for last-minute talks to break a deadlock that plunged Afghanistan into crisis as US-led troops end their 13-year war against the Taliban.
Ashraf Ghani -- who won June's run-off presidential vote, according to preliminary results -- will become president, with Abdullah Abdullah nominating the person to fill a new post of "chief executive officer" (CEO), which will be similar to prime minister.
Both Ghani and Abdullah claimed to have won the fraud-tainted election. The United Nations has pushed hard for a "national unity government" to avoid a return to the ethnic divisions of the 1990s civil war.
The two candidates signed the agreement at a ceremony inside the presidential palace, before they embraced each other and outgoing President Hamid Karzai began a speech.
Under the constitution, the president wields almost total control, and the new government structure will face a major test as the country's 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.
Independent Election Commission officials told AFP the official result would be released later Sunday, after the deal was signed.
The future of Afghanistan's relationship with the US-led NATO alliance also hangs in the balance after Karzai refused to sign a security pact to ensure a continued foreign military presence after this year.
NATO's top military commander said a unity government would enable the rapid conclusion of the pact.
"We are hoping for very fast signatures. And that would be important because it brings great stability to the conversation of our continued support," US General Philip Breedlove said on Saturday.
- Uneasy alliance? -
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 led to the Taliban taking power in Kabul in the 1990s.
Abdullah, a former anti-Taliban resistance fighter, draws his support from Tajiks and other northern ethnic groups. 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 will become "executive prime minister" in two years' time -- a major change to the way Afghanistan has been ruled since 2001.
Dividing up other official posts could also create friction after the long and mercurial reign of 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 an audit of all eight million ballot papers and then form a national unity government.
But Abdullah later abandoned the audit, saying it was failing to clean out fraud. He won April's first election round, only to see 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 Karzai and may be revived.
A total of 2,312 civilians were killed in the first eight months of this year, an increase of 15 percent from 2013.
About 41,000 NATO troops remain in Afghanistan, down from a peak of 150,000 in 2010, fighting alongside Afghan soldiers and police against the fierce Taliban insurgency.
NATO's combat mission will end in December. If an agreement is signed, a follow-on force of about 12,000 troops will stay into 2015 on training and support duties.
