Russia's use of a new hypersonic missile in Ukraine last week raised fears of an escalation of hostilities.
According to foreign media, the launch of the Oreshnik missile was presented by Vladimir Putin as a direct response to the US and Great Britain, which allowed Ukraine to use missiles they supplied to hit targets deep inside Russia.
However, a report from the New York Times suggests that there may have been very unusual efforts since then to avoid any escalation of tensions between Moscow and the West.
According to defense and military officials cited by the newspaper, Russian General Valery Gerasimov called Joe Biden's top military adviser last week and talked about how to manage escalating concerns between the two countries.
Contrary to Putin's claims, the report said Gerasimov told General Charles Brown, the chairman of the Joint Chiefs of Staff, that the launch of the Oreshnik ballistic missile was planned long before Washington agreed to allow Ukraine to use the US ATACMS to strike deeper into Russia.
Captain Jereal Dorsey, a spokesman for General Brown, said in a statement after being asked about the call that "at the request of General Gerasimov, General Brown agreed not to proactively announce the call."
He added that the two men "discussed a number of global and regional security issues, including the ongoing conflict in Ukraine."
The news sparked curiosity among analysts, who suggested it might have special significance.
Pavel Podvig, an expert on Russian nuclear forces and senior researcher at the UN Institute for Disarmament Research, said: "This is very interesting. A call to de-escalate?"
The Institute for the Study of War, meanwhile, noted that the transcript of the call showed that the Russian general's claims were at odds with the narrative pushed by the Russian president.
"Gerasimov's statement to Brown, if accurate, directly undermined this ongoing information operation by admitting that the Oreshnik launch was not connected to Ukrainian attacks on Russia with Western-supplied weapons, as Putin explicitly claimed in an emergency address immediately after the attack," analysts said.