Pakistan's opposition parties are demanding a parliamentary inquiry into a scandal in which the country's top scientist has confessed he sold nuclear secrets to Iran, Libya and North Korea.
The Pakistan Muslim League of former Prime Minister Nawaz Sharif accused President Pervez Musharraf of a cover-up and said the scandal had made Pakistan a "laughing stock".
The Pakistan People's Party of former Prime Minister Benazir Bhutto questioned the authenticity of the dramatic televised confession on Wednesday by Abdul Qadeer Khan, the father of the country's atomic weapons programme.
Mr Khan said he acted independently in leaking secrets as head of Pakistan's nuclear programme from the 1970s. Yesterday, Mr Musharraf pardoned the scientist, saying he remained a national hero despite passing secrets to Libya, Iran and North Korea.
However, Western diplomats and local commentators said Mr Khan could not have acted independently and that it appeared he had been used as a scapegoat for the army, which Mr Musharraf heads.
An opposition leader, Mr Chaudhry Nisar Ali Khan, said Musharraf was trying to save his government by putting the blame on Mr Khan and a few associates. He said this would not satisfy Pakistanis or critics abroad.
Mr Ali Khan is a former minister and a close aide of Mr Nawaz Sharif, who has lived in exile since being overthrown by Mr Musharraf in a bloodless 1999 coup.