Karzai said in an interview with The Associated Press that "sections of the international community" had undermined previous peace overtures to the Taliban by harassing people "even though they had quit the insurgency." He said these were people he convinced to leave the movement but did not offer specific examples.
It was Karzai's first interview since President Barack Obama announced a new strategy for the Afghan war, including 30,000 U.S. reinforcements. Obama said in his Tuesday address that if all went well, the U.S. could begin withdrawing troops in July 2011.
He said the July date would give an "impetus and a boost" for Afghans to work toward taking control of their own nation.
"We must talk to the Taliban as an Afghan necessity. The fight against terrorism and extremism cannot be won by fighting alone," Karzai said, adding that he would be willing to talk with the Taliban's reclusive chief Mullah Omar.
"Personally, I would definitely talk to Mullah Omar," he added. "Whatever it takes to bring peace to Afghanistan, I, as the Afghan president, will do it. But I am also aware that it cannot be done by me alone without the backing of the international community."
Karzai offered to talk with Omar soon after the Taliban was ousted in the U.S.-led invasion of 2001 but he backed off under U.S. pressure. Since then he has offered to talk with Omar or other Taliban members who were willing to quit the insurgency.
Those offers produced few results and no talks with the Taliban chief.
Omar disappeared after the collapse of the Taliban regime and has been rumored to be living in Pakistan, a charge the Pakistani government denies.
The Taliban have ruled out formal talks until the U.S. and other foreign troops leave the country.
Karzai appeared relaxed and confident, displaying an air of independence despite intense U.S. and international pressure to crack down on corruption and improve governance following this summer's contentious election that gave him a second term.
Karzai demanded the respect of Western leaders and defended the election, which U.N.-backed auditors said was tarnished by widespread fraud. He accused Western politicians and media of insulting him, his administration "and the Afghan people" by their repeated allegations of vote fraud.
He said the election was not fraudulent and that any corruption that occurred was not the work of Afghans.
"The Afghan elections were the best under the circumstances," he said. "We had no security in the south of the country. European observers called for the elections to be canceled even before the votes were counted."
He said the prospect of a U.S. military drawdown caused him no alarm.
"For Afghans, it's good that we are facing a deadline. We must begin to stand on our own feet. Even if it is with our own meager means - whatever those means may be. And we must begin to defend out own country. And if we, the Afghan people, cannot defend our country, ourselves, against an aggressor from within or without, then no matter what the rest of the world does with us, it will not produce the desired results," he said.
