Communications between the U.S. and Russia are essential for preventing an out-of-control crisis and a conduit exists for ongoing, high-level dialogue. But what is it really for?

According to The Wall Street Journal, White House National Security Advisor Jake Sullivan has been involved with a secretive “back channel” line of communication with top Russian officials as part of an effort by the U.S. and Russia to prevent the war in Ukraine from escalating into a nuclear conflict.

Among the officials named as representing the Russian conduit for this “back channel” are Yuri Ushakov, a senior foreign policy adviser to Russian President Vladimir Putin, and Nikolai Patrushev, the head of Russia’s security council.

In comments made shortly after the WSJ article appeared, Sullivan confirmed that he has been working to keep communication channels between the United States and Russia open despite the war in Ukraine, adding that it was “in the interests” of the White House to maintain contact with the Kremlin.

Speaking at the Economic Club of New York, Sullivan didn’t say that he himself has been engaged in the talks reported by the WSJ, only that the U.S. has “channels to communicate with the Russian Federation at senior levels.”

Sullivan has publicly availed himself of such channels in the past, conducting telephone calls with both Ushakov and Patrushev about European security and Ukraine on Dec. 20, 2021, and on March 16. Sullivan alluded to the existence of a “back channel” with Moscow in September when speculation was rampant about the possibility of Russia using tactical nuclear weapons against Ukraine.