The Washington Post reported that Russia's top military officials have been declining calls from their US counterparts since the country launched its invasion of Ukraine a month ago.
According to John Kirby, the Pentagon's spokesman, US Defense Secretary Lloyd Austin and Gen. Mark Milley have tried to reach out to their Russian counterparts.
Kirby said that the Russian leaders have so far declined to engage in the phone calls.
Russia and the US have set up a direct communication channel to avoid a conflict between their forces.
The refusal of Russia's military leaders to respond to their US counterparts suggests that Washington and Moscow's relationship could be in trouble.
On Monday, the Kremlin said President Joe Biden had put relations between the two countries on the verge of breakdown when he called Russian President Vladimir Putin a war criminal.
James Stavridis, NATO's former supreme allied commander, told The Post that there is a high risk of escalation without the firebreak of direct contact between the most senior officials.
Young people are flying in jets, operating warships, and conducting combat operations in the Ukrainian war. He said that they are not seasoned diplomats and their actions in the heat of operations can be misinterpreted.
We must avoid a scenario of NATO and Russia sleepwalking into war because senior leaders can't communicate with each other.
The war in Ukraine reached its one-month mark on Thursday, with Ukrainian forces continuing to repel Russia's attempts to advance into its major cities, contrary to Putin's reported belief that the entire campaign would be swift.
The Kremlin intensified its bombardment of major population centers. The military base in Lviv was hit by missiles on March 13, just 15 miles from where the US troops are in Poland.
According to a NATO official who spoke to the media on Wednesday, around 40,000 Russian troops have been injured, captured, or killed since the start of the war.