"The U.S. demanded a permanent military base from us and promised us two things in return," Karzai said, speaking exclusively to Anadolu Agency.
"The first was to support Afghanistan against external threats like Pakistan. And the second was to help the country improve its security situation and hence its economy," he said.
Karzai ruled Afghanistan for 10 years, in 2004-2014, after the Taliban regime was ousted by U.S.-led forces. His tenure was supported widely by the U.S. and its allies, and his anti-American comments come as something of a surprise.
The former president said that the U.S. had failed to combat terrorism in Afghanistan, despite its presence in the country since 2002, following the Sept. 11, 2001 attacks in New York.
He claimed that the U.S. military presence in Afghanistan was in fact helping terrorist groups like Daesh and the Taliban grow stronger.
"If this was not the case, the threat of terrorism would not escalate every day even when the U.S. is here [in Afghanistan]," Karzai said.
The non-nuclear "mother of all bombs" dropped by the U.S. military on a Daesh target in the eastern Nagarhar province this April was unacceptable, he said, arguing that the presence of foreign forces in Afghanistan was not helping the country.
The U.S., he said, had either backtracked on its promises, or it had failed in Afghanistan.
