Washington: Blaming the "Khan network" for proliferating nuclear centrifuge technology to North Korea, Iran and Libya, President George W Bush has said that nations around the world worked with the US to end the "criminal enterprise" headed by the father of Pakistan's nuclear bomb.

The extent and sophistication of proliferation networks, can be seen in the case of "a man named Abdul Qadeer Khan", Bush said at the National Defence University yesterday (Feb 11, 2004). "Governments around the world worked closely with us to unravel the Khan network, and to put an end to his criminal enterprise. Khan has confessed his crimes, and his top associates are out of business," Bush said unveiling his new campaign to fight spread of weapons of mass destruction.

Khan operated mostly out of Pakistan. He served as director of the network, its leading scientific mind as well as its primary salesman. Over past decade, he made frequent trips to consult with clients and to sell his expertise.

"The scientist and his associates sold the blueprints for centrifuges to enrich uranium, as well as a nuclear design stolen from the Pakistani Government. The network sold uranium hexafluoride, the gas that the centrifuge process can transform into enriched uranium for nuclear bombs," he said.

The network provided Iran, Libya and North Korea with designs for Pakistan's older centrifuges, as well as designs for more advanced and efficient models, Bush said.

This is the first time US has accused the network of supplying centrifuge technology. Earlier, it had not mentioned the specifics of the proliferated technology.

Bush said that the vast black-market operation run by A Q Khan highlighted the scope of the threat posed by proliferation.

"These dealers are motivated by greed, fanaticism and both. With the deadly technology and expertise on the market, there is the terrible possibility that terrorist groups could obtain the ultimate weapons," he said.

Bush for the first time accused the Pakistani scientist's network of supplying to North Korea the centrifuge technology for making nuclear weapons and outlined the role of US intelligence in dismantling and "penetrating" the network.

The US had previously said that it believed Khan's network was supplying weapons technology to North Korea, Libya and Iran but had not specified what.

Bush called for enhanced international efforts to curb the spread of nuclear technology and a range of actions including revamping the International Atomic Energy Agency (IAEA).

He proposed that by next year, only countries that have signed the additional protocol of the IAEA should be allowed to import equipment even for their civilian nuclear programmes.