Obama sends secret letter to Iran
Sources say #Obama noted Iran, U.S. both interested in defeating ISIS
United States is deep into talks with Iran about its nuclear capabilities
Sources say that's the main block to the countries cooperating on ISIS
Washington (CNN)-- President Barack Obama's administration is trying to open channels of communication with Iran regarding the war on ISIS.
Amid revelations that Obama sent a letter to Iran Supreme Leader Ayatollah Ali Khamenei last month pointing out the countries' shared interest in beating ISIS, a senior U.S. official and a Western diplomat tell CNN that Washington has gone through the Iraqis to communicate with Iran.
The conversations do not include taking joint military action against ISIS targets, the sources said, but are seen as necessary to avert conflict in U.S. and Iranian operations.
Senior White House adviser Dan Pfeiffer wouldn't address specific outreach efforts in an interview with CNN's Wolf Blitzer, but said: "We work very closely with the Iraqis and the Iraqis have a relationship with the Iranians."
The discussions through the Iraqis are informal and conducted on a case-by-case basis via the Iraqi military, the sources said. The channels have become necessary, the U.S. military official said, because the United States and Iran are now operating in the same spaces. As a result, "accommodations must be made indirectly," this official said. This includes airspace management, so U.S. and Iranian forces do not conflict while carrying out military operations in the same airspace, CNN was told.
The revelation of the communications channel comes even as the military and administration continue to insist it is not cooperating with the Iranians on strategy or intelligence.
"With respect to Iran, we're not coordinating with Iran, as you know," said Gen. Lloyd Austin, the head of U.S. Central Command, at an event moderated by CNN's Jake Tapper on Thursday, when asked how the United States prevents any accidental killing of Iranians who are on the ground advising Iraqi forces.
The White House also stressed it is not working alongside the Iranian military.
"The United States will not cooperate militarily with Iran in that effort. We won't share intelligence with them," White House spokesman Josh Earnest said Thursday when asked about another communication between President Obama and Iran's Supreme Leader.
Earnest would not acknowledge Obama's letter, saying he would not talk about the "private correspondence" of the President.