ISLAMABAD (Reuters) -- The Pakistani government reserves the right to appeal against a High Court ruling declaring disgraced nuclear scientist Abdul Qadeer Khan a free citizen, the foreign minister said.
The court ruling ending five years of house arrest for the man at the center of the world's most serious nuclear proliferation scandal raised concern in the United States and elsewhere about the risk of more proliferation.
Foreign Minister Shah Mehmood Qureshi, trying to calm those worries, said in Europe on the weekend the government had broken up Khan's network and he no longer had any say on, or access to, any area of Pakistan's nuclear program.
Qureshi also said the government reserved the right to appeal against the February 6 court ruling.
"That option is there," said Foreign Ministry spokesman Abdul Basit, referring to Qureshi's comments on a possible appeal. "But I would hasten to add that as far as we are concerned, as we have said time and again, this chapter is closed."
Khan, lionized by many Pakistanis as the father of the country's atomic bomb, was pardoned but placed under house arrest in 2004 by then President Pervez Musharraf soon after Khan made a televised confession to selling nuclear secrets to Iran, North Korea, and Libya.
Pakistani authorities denied any connection to Khan's proliferation network but never let foreign investigators question him, saying it had interrogated him and passed on all relevant information.
Nevertheless, U.S. and international experts investigating proliferation still want to question him.
Khan's detention had been relaxed over the past year. He was allowed to meet friends and traveled to Karachi at least once under tight security.
He also gave media interviews after a new government came to power in March. He recanted his 2004 confession saying he only took the blame in return for assurances from Musharraf's government that were never honored.
He did not elaborate but apparently irked the army by making comments about the smuggling of nuclear equipment that appeared to implicate the military and former army chief Musharraf, and was barred from speaking to reporters by a July court ruling.
U.S. Secretary of State Hillary Clinton said last week she was "very much concerned" about Khan's release.
White House spokesman Robert Gibbs said President Barack Obama wanted assurances from Pakistan the scientist would not be involved in nuclear proliferation.
India's Congress Party said the international community should consider declaring Pakistan a terrorist state in light of Khan's release. Pakistani Prime Minister Yousaf Raza Gilani dismissed that as Indian wishful thinking.
Khan, 72, who has been treated for prostate cancer, told reporters on February 6 shortly after the ruling that he had finished his nuclear work and wanted to devote his time to education.
He said he had no plan to travel abroad apart from Mecca, in Saudi Arabia, for a pilgrimage.
Khan remains under tight security though friends have been visiting him freely, said his wife, Henny Khan.