U.S. Defense Secretary Lloyd Austin learned of Russian President Vladimir Putin’s plan to put his nuclear forces on high alert from Putin’s announcement, a senior U.S. defense official said on a call with reporters Sunday. It’s just the latest sign there’s been a breakdown of communications and diplomacy between Russia, the United States, and other world powers at a crucial moment, as Russia launches an all-out assault in Ukraine and eyes taking Ukraine’s capital, Kyiv.

“He learned about it through the announcement. The announcement came right before the secretary was hosing one of his daily operations and policy synchronization meetings which was held this morning at 8:30,” the senior U.S. defense official said. “That announcement was discussed in the context of that meeting.”

Putin issued the alarming announcement about his nuclear forces on Sunday, claiming he was placing them on high alert in response to what he said were “aggressive” comments from NATO powers. The senior U.S. defense official would not touch on the status of U.S. nuclear forces, but is confident in the United States’ ability to defend the country, allies, and partners. “It is always a priority to be able to defend the homeland and to make sure our strategic deterrence is capable, viable and ready at all times,” the official said. The news comes just as Ukrainian President Zelensky’s office announced Ukraine has agreed to talks with Russian officials.