Today, however, with U.S.-Russia relations at their lowest point since the end of the Cold War and new talk of nuclear contingencies emerging from both sides, Moscow's envoy in Washington has told Newsweek that no such communication now exists, setting the stage for a new and dangerous era for the two nations, and for the rest of the world.

Anatoly Antonov, Russia's ambassador to the U.S., recalled the words of his predecessor, Anatoly Dobrynin, who said in his time that "the Cuban missile crisis revealed the mortal danger of a direct armed confrontation of the two great powers, a confrontation headed off on the brink of war thanks to both sides' timely and agonizing realization of the disastrous consequences."

Antonov also quoted U.S. President John F. Kennedy, who, shortly after the October 1962 crisis resolved with an agreement for Moscow to withdraw missiles from Cuba and Washington to pull back its own weapons in Turkey, told Soviet Council of Ministers First Deputy Chairman Anastas Mikoyan, "What we have now is, although our two countries do not challenge each other directly, we keep running into each other almost everywhere, which in our nuclear age is fraught with serious dangers for world peace."

"The undeniable advantage of that time was a continuously operating confidential channel between Anatoly Dobrynin and Robert Kennedy," he added, referring to Attorney General Robert Kennedy, the president's brother and adviser, who played a critical role in negotiating an end to the affair. "It allowed the Kremlin and the White House to relay information to each other in a timely manner, do appropriate analysis and clarify positions of the two states."

But Antonov said the two powers were now at a considerable disadvantage, as "today, the infrastructure of our communication with the Americans has been demolished."

The last reported conversation between Biden and his Russian counterpart Vladimir Putin occurred on February 12, two weeks before the Russian leader launched a war against neighboring Ukraine. The Kremlin's decision came after months of failed talks in which Moscow had demanded that Washington and its allies withdraw military infrastructure from former Soviet states now members of the NATO alliance.