CIA director: Iran's nuclear program advancing at "worrisome pace"

Iran's nuclear enrichment program is more advanced than previously known and "if they chose to cross that line," Tehran would only need a "matter of weeks" to enrich uranium capable of powering a nuclear weapon, CIA director William Burns told CBS News in an exclusive interview with "Face the Nation" that aired Sunday.   

"To the best of our knowledge, we don't believe that the Supreme Leader in Iran has yet made a decision to resume the weaponization program that we judge that they suspended or stopped at the end of 2003," Burns told "Face the Nation" moderator Margaret Brennan. "But the other two legs of the stool, meaning enrichment programs, they've obviously advanced very far." 

Burns noted that Tehran has also been advancing its missile systems, and is now nearing the threshold of being a nuclear state, though it has not resumed weaponization.

U.S. intelligence analysts believed Iran paused working on nuclear weapons in 2003, but that they have continued to develop nuclear technology and expertise, including improved abilities to enrich uranium which can be used as nuclear fuel. Uranium enriched to 90% purity can be used to manufacture nuclear weapons. 

Last week, Bloomberg reported that Iran possesses uranium at 84% purity. The International Atomic Energy Agency (IAEA) said it was aware of the reports and would discuss with Iran the results of recent verification activities that the UN nuclear watchdog had performed.

Under the 2015 Joint Comprehensive Plan of Action (JCPOA), Iran committed to limit uranium enrichment to 3.67% purity, a level which could fuel nuclear power plants. In exchange, the other world powers that signed onto the deal agreed to lift economic sanctions that had strangled Iran's economy. The Obama-era landmark deal grew out of a secret backchannel that Burns, then deputy Secretary of State, initiated with Iran in 2013.

But former President Donald Trump pulled the U.S. out of the agreement in 2018. Since then, Tehran announced enrichment levels up to 60% purity. Talks to bring Washington back into agreement with Tehran began in 2021, but have since faltered. The Biden administration has acknowledged that diplomacy remains on deep freeze.

"They've advanced very far to the point where it would only be a matter of weeks before they can enrich to 90%, if they chose to cross that line," Burns said on "Face the Nation." "In terms of their missile systems, their ability to deliver a nuclear weapon, once they developed it, has also been advancing as well." 

Burns reiterated that the CIA has no knowledge that Iran has resumed their nuclear weapons program. However, he said, "the other dimensions of this challenge, I think, are growing at a worrisome pace."

In the interview with Brennan, Burns also expressed concern about the growing partnership between Russia and Iran.

"It's moving at a pretty fast clip in a very dangerous direction right now," Burns said about the relationship between the two countries. "We know that the Iranians have already provided hundreds of armed drones to the Russians, which they're using to inflict pain on Ukrainian civilians and Ukrainian civilian infrastructure. We know that they've provided you know, ammunition for artillery and for tanks as well."

According to Burns, aid shared between Russia and Iran may go beyond the supply of drones and ammunition. 

"What we also see are signs that…Russia is proposing to help the Iranians on their missile program and also at least considering the possibility of providing fighter aircraft to Iran as well," Burns said. 

Iran is not the only country to have provided assistance to Russia since the invasion of Ukraine in February 2022. North Korea has as well. China also has provided non-lethal support to the Russian Federation, and according to Burns, may also be considering sending lethal aid.