Talks between Brazil and the United Nations regarding inspections of a Brazilian nuclear facility hit a snag Thursday, with the two sides disagreeing on the exact terms of what parts of plants inspectors could view.

The disagreement contradicts earlier reports that South America's largest producer of uranium and the international body were on the same page for U.N. inspections originally set for next month.

The United Nation's nuclear agency, the International Atomic Energy Agency, or IAEA, wants to be sure that Brazil is in compliance with international accords for refining uranium, making certain that it cannot be used for the production of nuclear weapons.

We made some progress, but ... we continue to be in discussions with Brazilian authorities on this subject, IAEA spokesman Mark Gwozdecky said Thursday from the agency's headquarters in Vienna.

Gwozdecky did maintain his original assertion that IAEA inspectors would arrive in Brazil to view a nuclear refinement plant in Resende, in Rio de Janeiro state. Under international nuclear regulations, the plant -- which has yet to begin process uranium -- cannot begin doing so until it passes inspection.

Thursday's exchange between the two side of Brazil's nuclear issue caught the attention of the U.S. State Department. An official from the department told United Press International that the Bush administration urged Brazil and IAEA to work together to come to an agreement on inspections.

Of course, this isn't the first time there's been an impasse on the matter.

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.

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 technology 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 projecting its technology does have some worried that it could be harboring secret nuclear ambitions, namely the production of nuclear weapons.

In its defense, Brazil officially swore off the development of nuclear weapons in the 1990s during the administration of then President Fernando Henrique Cardoso.

Cardoso's successor, however, 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 that 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 Brazil's current Science and Technology Minister 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.

According to Brazil's Nuclear Industries, the country possesses the fourth-largest uranium reserves in the world.

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.