"No scientist from any other country has helped in this regard," visiting Iranian Deputy Foreign Minister Mohsin Aminzadeh was quoted as telling reporters here by the state-run Associated Press of Pakistan (APP).
Referring to Iran's talks with the International Atomic Energy Agency (IAEA), Aminzadeh said Iran only gave the global nuclear watchdog information about five individuals -- three Europeans and two from this region -- who helped Iran buy equipment required for its nuclear programme, APP said.
APP did not specify what Aminzadeh meant when he said "this region", but he said the two "had been acting as brokers, they were businessmen who as intermediaries helped us through."
He said it is normal business practice to procure equipment from anywhere in the world and Iran did not contravene the norms.
He called the alleged Pakistan-Iran nuclear cooperation a "fabrication by media", APP said.
Two Pakistani nuclear scientists, Yasin Chohan and Farooq Mohammad, directors of the country's key Kahuta Research Laboratory (KRL), were taken from their homes in early December for questioning about their links with Iran's nuclear programme.
Chohan has since returned home but Farooq is still being questioned.
The creator of Pakistan's nuclear bomb, Abdul Qadeer Khan, had also been questioned.
Pakistan foreign ministry spokesman Masood Khan said Monday "a very small number of scientists" were being questioned.
"When the government of Iran shared some information with us and subsequently the International Atomic Energy Agency asked for our cooperation, we started these debriefing sessions," Khan said earlier.
The New York Times reported last month that information Iran turned over to the IAEA had strengthened suspicions that Pakistan sold key nuclear secrets to Iran.
Pakistan's suspected role in providing centrifuge designs to Iran was also revealed by the Washington Post, which said the blueprints provided a "tremendous boost" to Iran's pursuit of nuclear weapons.
Centrifuges can be used to enrich uranium, spinning it at supersonic speeds to produce a concentrated material used to make nuclear weapons.
Pakistan last week also denied another New York Times report that some of its scientists may have provided Libya with technology to enrich uranium for use in nuclear weapons.
Islamabad, which went public as a nuclear power in May 1998 when it conducted underground nuclear tests, has consistently denied reports that it has exported its nuclear know-how.
President Pervez Musharraf has rejected the allegations as a smear campaign.