Asked whether he had suspicions that US bases were being used to aid the IS, he said: "I have more than suspicions." he said.
'The former president claimed in an exclusive interview with Russia Today in London he had heard reports, albeit unconfirmed, that the IS was being supplied with helicopters.
"'How unmarked non-military colour helicopters supply these people, not only in one part of the country but in many regions," Mr Karzai wondered. "And this is a daily occurrence,"
He also claimed that the terror group has been able to spread its tentacles in the country just under the nose of the US forces and the CIA.
Asked if he agreed with a notion that the IS was a US construct, he replied: "Absolutely."
Hamid Karzai said Afghan extremism had grown stronger since the 9/11 terror attack, although the US had spent billions of dollars in the "war against terror".
"We don't want our country to be bombed with huge, destructive weapons. We want peace."
The former president also claimed that the US did not use the MOAB (mother of all bombs) in Afghanistan to defeat terrorists, but for some "other reasons".
"The bomb was meant to show to North Korea the US might. Whatever the purpose was, it was an atrocity on the Afghan people.
"You don't drop a bomb because you want to kill a few individuals. You ruined the environment, the village, the air and the water," Mr Karzai observed..