Sometimes being close just isn’t enough, and John Kerry of all people should know that. The secretary of State said Tuesday that the world’s powers and Iran came “extremely close” to a deal over Iran’s nuclear program, but there were still lingering doubts that the Islamic Republic might pursue a nuclear program. “We haven’t been speaking in 35 years,” Kerry told the BBC. “We just talked more in 30 hours than we have in 30 years prior.” It’s still unclear what exactly caused the talks to break down—early reports said France adopted a hard line on a heavy-water plant being built in Arak, while U.S. diplomats have said a major sticking point was the Iranian government’s insistence on its “right” to enriched uranium. Kerry said Iran backed out of a deal on the last day of talks. Diplomats are expected to meet again Nov. 20 to pick up where they left off.