Pakistan's disgraced atomic scientist A Q Khan, under house arrest for the past four years after admitting to proliferating nuclear technology, has said that he is under 'illegal detention' and hopes that the new government will soon lift restrictions on his movement.

'My health is deteriorating and the claims of the government about my physical well-being do not carry weight,' 72-year-old Khan said in probably his first interview since

his detention in February 2004 with Urdu newspaper Nawa-i-Waqt.

The main cause of his poor health is his 'solitary confinement', claimed Khan, who was hospitalised briefly last month and has undergone several medical check-ups in the past few weeks.

Refuting the impression that he had been detained due to security concerns, he said: 'It is nothing but only a lame excuse by the government.'

During the interview, which the newspaper said was conducted 'through special means', Khan ran out of breath and had difficulty in speaking.

Khan, who was apparently bitter about the attitude of the government, said it was an 'irony of fate' that he was being kept in solitary confinement.

Rebutting the government's logic behind his detention, Khan said: 'It is simply irrational. I was roaming around the world freely at times when in 1979 numerous fake cases had been registered against me in Holland and I faced no security threat.'

Asked about his health, Khan replied: 'My lower limbs are losing vitality and I am suffering from extreme lethargy.'

Khan said his blood pressure was becoming 'unmanageable day by day'.

April one was Khan's 72nd birthday and lawyers in Lahore [Images] celebrated the occasion and demanded his immediate release. The Save Judiciary Committee in the Lahore High Court has been demanding Khan's release for over a year.

Despite his public admission on state-run television of running a nuclear proliferation ring, Khan is regarded as a national hero in Pakistan and several political parties, including the PML-N that is part of the new ruling coalition, have said he should be freed.

Officials of Pakistan's nuclear establishment have said that Khan is kept under detention for his own security. Khan, who is currently detained in his home in a quiet area of central Islamabad, is allowed to meet only selected visitors only after they are vetted by security agencies.

Pakistani authorities have shared information gathered from Khan with the International Atomic Energy Agency but have refused to give foreign investigators direct access to the scientist who admitted to proliferating nuclear secrets and materials to Iran, North Korea and Libya.

Political heavyweights like PML-N chief and former premier Nawaz Sharif had called for Khan's release during the election campaign but have since distanced themselves from demands.

Khan reportedly stole plans for centrifuges used to produce enriched uranium, a key ingredient in nuclear weapons, while working in the Dutch firm in the 1970s.

He underwent surgery for prostrate cancer two years ago and was recently treated for various ailments, including low blood pressure and an infection.