The majority of the 66,000 U.S. troops in Afghanistan are due to leave in 2014, though between 6,000 and 15,000 will possibly remain in the country to train Afghan forces and pursue insurgents, U.S. commanders said.
U.S. President Barack Obama said any support troops left in Afghanistan after the withdrawal must have immunity so they are not subjected to Afghan law.
Karzai, speaking at a news conference in Afghanistan after his return from a four-day visit with Obama in the United States, said it would take at least eight to nine months to reach an immunity agreement.
Karzai said he believes Afghanistan will be more secure and a "better place" once NATO and other foreign troops leave, Khaama Press reported.
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