Speaking to BBC ahead of Thursday's conference in London, Karzai said although the Afghanistan police and soldiers could be trained in another five to 10 years, it would take much longer to sustain the efforts put in by the foreign troops.
During his speech at the international conference on Afghanistan that started on Thursday -- which aims to gain international support for Karzai's reconciliation plan -- Karzai urged for serious moves toward an "Afghan led, Afghan run" nation.
He acknowledged the continuing need for both foreign aid and troops in the country, but said the people aspired for an "Afghan leadership and Afghan ownership".
In his address to delegates from over 70 nations, Karzai laid out a six-point framework with peace, reconciliation and security as priorities for Afghanistan.
"Peace and security in the world is inextricably linked to peace and security in Afghanistan," he said.
He urged Afghanistan and its Western supporters to "reach out to all of our countrymen, especially our disenchanted brothers who are not part of the Al Qaeda."
Kazai asked the United Nations to take further steps to remove Taliban officials from its sanctions' list, as, he said, he hoped to reintegrate some Taliban fighters into society.
The UN approved the removal of five former Taliban officials from the list on Monday including Wakil Ahmad Muttawakil, a former foreign minister and confidant of Afghan Taliban leader Mullah Mohammed Omar.
Karzai hoped that the one-day summit would give a renewed momentum to the nation-building process in Afghanistan.
British Prime Minister Gordon Brown said the conference marked "the beginning of the transition process" and warned the Qaeda that they would be defeated.
United Nations secretary general Ban Ki-Moon and US secretary of state Hillary Clinton are among the delegates for the conference.Pak envious of India's dominance in Afghanistan?
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