Saif al-Islam Qadhafi told the Arabic newspaper Al-Sharq al-Awsat that Libya welcomed British and American "experts in various fields, but not forces in the military sense".
Britain's Sunday Times newspaper had quoted Saif al-Islam as saying there would be "no problem" with British or US troops being stationed in Libya.
"We are giving up our weapons, so we need an international umbrella for protection," he was quoted as saying.
He also told the newspaper Libya had paid Pakistani scientists "millions of pounds" for plans to make a nuclear bomb.
He said Libya had spent $40 million in total on its efforts to acquire a nuclear capability.
Libya, long on a US list of sponsors of terrorism, said last month it was abandoning plans to build an atomic bomb and other weapons of mass destruction. It now wants trading benefits, including an end to US sanctions.
Analysts say Qadhafi is grooming Saif al-Islam to succeed him.
The son was quoted in al-Sharq al-Awsat recently saying British Prime Minister Tony Blair and US President George Bush would visit Libya early next year.