(VOVworld) - Supreme Leader Ayatollah Ali Khamenei reiterated on Wednesday Iran’s “red lines” in negotiations with world powers over its controversial nuclear program, which is due to resume next week in Vienna. Khamenei outlined 11 points to be observed by negotiators before Iran will sign an accord. One of the stipulations includes “the absolute need for Iran’s uranium enrichment capacity to be 190,000 SWU (Separate Work Units)”, close to 20 times its current processing ability. Iranian officials say this is needed to produce fuel for its Bushehr reactor, which is being provided by Russia until 2021. The US and other Western states, however, want Iran to decrease its enrichment capability.