United Nations nuclear inspectors are expected to release the latest report on Iran's nuclear program this week.
Diplomatic sources in Vienna say the International Atomic Energy Agency is under pressure from Western nations to declassify even more intelligence reports on Iran's nuclear activities.
They say the countries are trying to build a stronger case for new sanctions against Tehran.
Western nations accuse Iran of trying to build a nuclear bomb, but Tehran says it is pursuing nuclear energy.
Meanwhile, Iranian officials concerned about possible air strikes against their nuclear facilities are pushing for a U.N. ban on such attacks.
The proposal reportedly has the support of the 118-nation nonaligned movement. It is expected to be submitted when IAEA nations meet next month.
The IAEA passed a resolution in 1990 that banned military strikes on peaceful nuclear facilities.
Israeli warplanes destroyed Iraq's only nuclear reactor in 1981 and two years ago bombed a suspected nuclear reactor site in Syria. Analysts say Iran wants to reduce the chances of a similar attack by trying to win passage of another U.N. ban.
While Iran denies it has a nuclear weapons program, it has ignored U.N. resolutions to stop enriching uranium, a key component of nuclear bombs.
An IAEA report in June said Tehran is using 5,000 centrifuges to enrich uranium. Diplomats this week said Iran has installed an additional 2,000 centrifuges, although it has not increased the number involved in enrichment.
Washington has given Iran until the opening of the U.N. General Assembly meeting in September to accept an offer to discuss incentives with six Western nations, in exchange for stopping its uranium enrichment.
French President Nicolas Sarkozy said Wednesday he would support stronger sanctions against Iran if Tehran does not halt its nuclear activities.
Some information for this report was provided by AP and Reuters.