A draft accord released by the Afghan government appears to meet U.S. demands on such controversial issues as whether U.S. troops would unilaterally conduct counterterrorism operations, enter Afghan homes or protect the country from outside attack.
Without the accord, Washington has warned it could withdraw its troops by the end of next year and leave Afghan forces to fight a Taliban-led insurgency without their help.
Thousands of Afghan dignitaries and elders are due to convene in a giant tent in the capital Kabul on Thursday to debate the fate of U.S. forces after a 2014 drawdown of a multinational NATO force.
"We have reached an agreement as to the final language of the bilateral security agreement that will be placed before the Loya Jirga tomorrow," U.S. Secretary of State John Kerry told reporters in the U.S. capital, referring to the gathering.
Intense negotiations between Kabul and Washington have provoked frustration among the Afghan tribal and political elders who made perilous journeys from all over the country to the capital Kabul for a grand assembly to debate the pact.
Efforts to finalise the pact stalled on Tuesday amid disagreement over whether U.S. President Barack Obama had agreed to issue a letter acknowledging mistakes made during the 12-year Afghan war.
Kerry denied any discussion about the possibility of a U.S. apology to Afghanistan for U.S. mistakes or Afghan civilian casualties, a move that would likely draw widespread anger in the United States.
"The important thing for people to understand is there has never been a discussion of or the word 'apology' used in our discussions whatsoever," Kerry said, adding that Afghan President Hamid Karzai had also not asked for an apology.
It was unclear where the notion of an apology originated.
A U.S. official said that when Kerry declined Karzai's invitation to attend the Loya Jirga, the Afghan leader asked for U.S. reassurances to the council on the future security relationship that would also address civilian casualties.
Kerry suggested outlining the U.S. position in a letter. When Karzai asked if the letter could come from Obama, Kerry said he would check, this official added.
The secretary of state on Wednesday said "it is up to President Obama and the White House to address any issues with respect to any possible communication" between the two presidents.
Susan Rice, Obama's national security adviser, insisted on Tuesday that an apology was "not on the table."
The 24-page draft agreement posted on the Afghan foreign ministry's website suggested that the United States had got its way on several controversial issues:
- The pact does not commit the United States to defend Afghanistan from foreign attack, saying rather that Washington "shall regard with grave concern any external aggression;"
- It says U.S. forces "shall not target Afghan civilians, including in their homes" - phrasing that suggests they could enter Afghan homes as long as civilians were not the objective;
- It says U.S. military operations may be needed to fight al Qaeda and says the two countries will cooperate "with the intention of protecting U.S. and Afghan national interests without unilateral U.S. military counterterrorism operations," phrasing that does not absolutely rule out the United States acting on its own.
- It gives the United States the exclusive right to try U.S. forces for criminal or civilian offences in Afghanistan and it grants U.S. military aircraft unfettered overflight rights.
Violence ahead of gathering
U.S. forces arrived in Afghanistan soon after the Sept. 11, 2001, attacks on New York and Washington and toppled its Taliban-led government which harboured the al Qaeda leaders.
Their presence has generated deep enmity among some Afghans who resent what they see as U.S. violations of their sovereignty and civilian casualties flowing from U.S. military operations.
The drawdown of Western troops has allowed tentative peace overtures between Kabul and the Taliban to gather pace, and Afghan officials arrived in Pakistan on Wednesday to initiate talks.
The Taliban have nonetheless condemned the Loya Jirga as a farce, and security has been tight in Kabul following a suicide bomb attack near the assembly ground over the weekend.
Insurgents fired two rockets at the tent where the last Loya Jirga was last held in 2011, but missed the delegates.
If the two sides cannot agree on a pact, Karzai has suggested submitting different versions of the document for the Loya Jirga to decide on. That caused confusion among Jirga members.
Khan Ali Rotman, who runs a Kabul youth organisation, said if the pact was not in Afghanistan's national interests, "we will raise our voice and not vote for it".
But a Kabul senator, Khan Mohammad Belaghi, said Afghanistan had no choice but to sign:
"We have to have a partnership with a country like the United States and we will vote in favour of it because it can protect us from threats from neighbouring countries, especially Pakistan, and the Taliban."
Violence spiralled on the eve of the meeting, with the Taliban attacking two high-ranking police officials.
Gunmen ambushed and killed the police chief of Marja district in the southern province of Helmand on his way to work, said Omar Zwak, a spokesman for the provincial governor.
Also in the south, guards shot dead a suicide bomber trying to force his way inside the house of the Kandahar provincial police chief, said Hamid Zia Durrani, a spokesman for the police. Later a bomb exploded at a hotel a few doors away, killing three and wounding 14, he said.
(Additional reporting by Mirwais Harooni, Katharine Houreld in Kabul and Sarwar Amani in Kandahar, and Dylan Welch in Islamabad; writing by Maria Golovnina and Lesley Wroughton; editing by Ralph Boulton and Jackie Frank)