Libya was disgraced Pakistani scientist A Q Khan's "best customer", according to US Vice President Dick Cheney.

When the US was considering what to do with the threat posed by Iraq, "we had the difficult problem with the proliferation of nuclear weapons technology. At the time, it was known to us through intelligence sources that there was an organisation headed up by a man named A Q Khan", Cheney said at a town hall meeting in Hot Springs, Arkansas.

Complete Coverage: Pakistan's nuclear bazaar

"Khan was the father of the Pakistan nuclear programme. He had developed nuclear weapons for Pakistan. Once he completed that process, he then diverted that suppliers' network that he put together and began to supply nuclear weapons technology to some of the world's less attractive regimes: North Korea, Iran and Libya," he said. 

Khan was "spreading the world's deadliest technology to some of the world's most questionable regimes", he added.

Libyan leader Moammar Ghadafi, Khan's "best customer", was spending "millions to require that capability, that technology", he said.