Brazil's nuclear program was once again subject to international scrutiny Thursday following U.N. speculation that a Pakistani scientist who supplied sensitive nuclear technology to North Korea, Libya and Iran, also divulged the information to the South American nation.

A former U.S. Defense Department official told leading Brazilian newspaper Estado de Sao Paulo that the reason the United Nations was interested in inspection a new nuclear facility in Resende, Rio de Janeiro, was speculation that the technology at the plant was supplied by former Pakistani nuclear program head Abdul Qadeer Khan, who provided nuclear technology to several rogue nations over the years.

Last week Brazil and the United Nation's nuclear agency, the International Atomic Energy Agency, or IAEA, clashed over the terms of inspections at the Resende plant set for October.

Under international law, the plant cannot begin to process uranium until it passes IAEA inspection. Brazil has the world's fourth largest reserves of the raw material used in nuclear power plants and weaponry.

Brazilian officials at the Minister of Science and Technology said they would allow IAEA inspectors in certain parts of the plant but not others to protect Brazilian innovations in uranium processing for fuel.

Henry Sokolski, head of the Washington-based Nonproliferation Policy Education Center, told Estado that IAEA officials harbor concerns that the source of the technology of (Brazilian) centrifuges was Kahn.

Some Brazilian scientists are outraged by the allegations that Brazil obtained the technology for its Resende plant from Pakistan.

It is absurd to speculate that Brazil had bought old concepts adopted by Pakistan when it has something superior at its disposal, said physicist Fernando Barros to Estado.

Despite Brazil's ardent denials, Washington is urging Brazil to cooperate with the IAEA.

An official from the U.S. State Department told United Press International last week that the Bush administration urged Brazil and IAEA to work together to come to an agreement on inspections.

This, of course, isn't the first time that Brazil's been the subject of international speculation regarding its nuclear program.

In April, Brazil was accused of refusing to allow U.N. nuclear inspectors to examine the Rio facility in February and March of this year.

The plant is legal under international treaties, but is still subject to U.N. inspections. IAEA inspectors were prevented from seeing certain portions of the plant.

Brazilian officials said the inspections were unnecessary and intrusive since Brazil formally abstained from nuclear weapon development in the 1990s during the administration of then President Fernando Henrique Cardoso.

Despite their objections, Brazil officials say they will allow IAEA inspectors to view some parts of the plant, although not others, citing concerns about protecting Brazilian technological secrets.

Earlier this year Brazilian Defense Minister Jose Viegas defended the nation's right to secrecy, saying at no time did this attitude signify an impediment to the inspections.

Brazil's penchant for protecting its technology does have some worried that it could be harboring secret nuclear ambitions, namely the production of nuclear weapons.

Cardoso's successor, current President Luiz Inacio Lula da Silva, made remarks during his 2002 presidential race that continued to resound with Washington, the United Nations and the IAEA.

During his run up to the presidency in 2002, Lula said the 1970 treat was unfair. If someone asks me to disarm and keep a slingshot while he comes at me with a cannon, what good does that do? he asked in a campaign speech. These remarks quickly became infamous among diplomatic circles in Washington. The Brazilian president later clarified his position, saying that he had no intention of restarting Brazil's weapons program.

Concerns arose anew in October 2003 when then Science and Technology Minister Roberto Amaral said Brazil would join the select group of nations capable of refining uranium via ultra-centrifugation, part of the weapons-grade production process.

Amaral was reprimanded by Lula for the comments and later replaced by Eduardo Campos. Despite the comments, it's not the creation of nuclear weapons that appears to concern inspectors, rather the potential for Brazil to sell refined material to other nations.

There is also Brazil's recent history of selling uranium that still concerns Washington and international inspectors. From 1979-1990 Brazil sold several tons of uranium to Iraq while the nation was under the rule of former dictator Saddam Hussein. According to Brazilians experts, additional uranium was sent to Iraq in off-the-books deals in exchange for oil during the same period.

Lula has announced that Brazil intends to expand its enrichment capacities to sell low-grade uranium to other nations. The 1970 treaty permits this, though it would surely raises red flags at the IAEA and in Washington.