"Pakistan is a responsible member of the international community. We have been cooperating with the IAEA (UN nuclear watchdog) and sharing information," said Khurshid Mahmud Kasuri, who is on a two-day visit to Tehran.

"Of course we will cooperate and are cooperating," he told a press conference.

"But as far as inspections of Pakistan are concerned, that is out of the question. We are not a signatory" of the nuclear non-proliferation treaty (NPT), said Kasuri.

Pakistan's cooperation with the International Atomic Energy Agencyis crucial in resolving one of the main outstanding questions related to Iran's nuclear programme.

IAEA inspectors have found traces of highly-enriched uranium inside Iran, leading to suspicions the Islamic republic has been trying to enrich uranium for nuclear bombs and not atomic energy as it insists.

But Tehran maintains the traces found their way into the country on equipment bought on an international black market operated by Pakistan's disgraced former nuclear chief, Abdul Qadeer Khan.

The IAEA wants to take so-called "environmental samples" from Pakistan to compare them with those found in Iran.

WAR.WIRE