with a yield of twenty to thirty kilotons and a second with a yield of twelve kilotons. The same report revealed that Brazil's military regime secretly exported eight tons of uranium to Iraq in 1981. In 1991, Brazil and Argentina renounced their nuclear rivalry. On 13 December 1991, they signed the Quadripartite agreement, at the IAEA headquarters, creating the Brazilian–Argentine Agency for Accounting and Control of Nuclear Materials and allowing fullscope IAEA safeguards of Argentine and Brazilian nuclear installations. Brazil officially opened the Resende enrichment plant in May 2006. Brazil's enrichment technology development, and the plant itself, involved substantial discussions with the IAEA and its constituent nations. The dispute came down to whether IAEA inspectors would be allowed to inspect the machines themselves. The Brazilian government did not allow the inspection of the centrifugal cascade halls, arguing that this would reveal technological secrets (probably relating to the use of a magnetic lower bearing in place of the more common mechanical bearing). The Brazilian authorities stated that, as Brazil is not part of any "axis of evil", the pressure for full access to inspection - even in universities - could be construed as an attempt to pirate industrial secrets. They also claimed that their technology is better than that of the United States and France, mainly because the centrifugal axis is not mechanical, but electromagnetic. Eventually, after extensive negotiations, agreement was reached that while not directly inspecting the centrifuges, the IAEA would inspect the composition of the gas entering and leaving the centrifuge. Then–U.S. Secretary of State Colin Powell stated in 2004 that he was sure that Brazil had no plans to develop nuclear weapons. Technological capability It is likely that Brazil has retained the technological capacity and knowhow to produce and deliver a nuclear weapon. Experts at the Los Alamos National Laboratory have concluded that in view of its previous nuclear activities, Brazil is in a position to produce nuclear weapons within three years. If Brazil decided to pursue a nuclear weapon, the centrifuges at the Resende enrichment plant could be reconfigured to produce highly enriched uranium for nuclear weapons. Even a small enrichment plant like Resende could produce several nuclear weapons per year, but only if Brazil was willing to do so openly. The Brazilian Navy is currently developing a nuclear submarine fleet, and in 2007 authorised the construction of a prototype submarine propulsion reactor. In 2008, France agreed