Afghanistan's Electoral Complaints Commission has called on presidential candidate Abdullah Abdullah to work with authorities who are investigating his allegations of widespread election fraud.
Commission chief Abdul Satar Sadat said in Kabul on July 9 that Abdullah's campaign team should speak with the commission about his accusations of fraud rather than continuing his boycott of the process.
Preliminary results show Ashraf Ghani leading Abdullah by about 1 million votes.
But the U.S. State Department has said up to 3 million of the 8 million ballots counted by Afghan election officials could be involved in an audit of votes from 7,000 polling stations that have been challenged -- enough to alter the outcome.
Abdullah says massive fraud is the reason that the preliminary results show him trailing Ghani.
On July 8, Abdullah told a rally of his supporters that he was the victor and should be inaugurated as Afghanistan's next president.
"We are the winner of this round of election without any doubt," he said. "We will not allow the fraudulent government to rule this country even for a day, without any doubt."
But he said his campaign team does not want "civil war" or "a crisis," and called for "stability, national unity, not division."
Abdullah also told supporters they should not stage protests until after he meets in Kabul with U.S. Secretary of State John Kerry on July 11 to discuss the dispute.
Abdullah also acknowledged calls from his supporters to announce his government. But he told them he will decide what action he will take after his talks with Kerry on July 11.
U.S. President Barack Obama has telephoned Abdullah and Ghani separately to tell them both that the United States expects the allegations of election fraud to be thoroughly investigated.
Obama also urged both candidates to stay calm and seek a resolution that doesn't undermine national unity.
Obama also warned both candidates that if "violent or extra-constitutional" means are used, Washington would end its assistance to Afghanistan.
NATO Secretary-General Anders Fogh Rasmussen said that wrangling over the election results must be resolved in time for a new president to sign a security pact with NATO by September.
Rasmussen said if the pact is not signed before a NATO summit in Wales in early September, the alliance will have "severe" problems planning a training mission in Afghanistan after 2014.
Afghan President Hamid Karzai has refused to sign the pact before he leaves office, leaving the task to the next elected president.
But the process of investigating fraud complaints could delay the final official results.
The Afghan Independent Election Commission has set a deadline of July 22 to announce the final results.
An inauguration has been scheduled for August 2.