The announcement also came amid reports the US and Russia were negotiating a deal to extend a nuclear arms reduction treaty due to expire on Thursday.
Throughout decades of crisis and confrontation, the US and Russia have often kept channels of communication open between their armed forces.
The aim was to avoid misunderstanding and escalation.
But those contacts were suspended in 2021 shortly before Russia’s full-scale invasion of Ukraine.
Since then there have been flashpoints involving Russian drones and warplanes entering Nato airspace, and US unmanned aircraft over Syria and the Black Sea.
The new agreement was reached during talks in the UAE between US General Alexus Grynkewich, America’s and Nato’s top general in Europe, and senior Russian and Ukrainian military officials.
US European Command said: “Maintaining dialogue between militaries is an important factor in global stability and peace, which can only be achieved through strength, and provides a means for increased transparency and de-escalation.
“This channel will provide a consistent military-to-military contact as the parties continue to work towards a lasting peace.”
The aim, it said, was “to avoid miscalculation and to provide a means for avoiding unintended escalation by either side”.
There has been some contact between the US, Nato and Russia military officers in recent years but this announcement means a regular dialogue between senior commanders will be re-established.
Russia said on Thursday it regretted the expiry of the New Start treaty, external with the US but was still ready to talk.
The Kremlin has offered to extend the treaty and its spokesman, Dmitry Peskov, said Russia would engage in dialogue with the US if it responded positively.
On Thursday, Trump wrote on social media: “Rather than extend “NEW START” (A badly negotiated deal by the United States that, aside from everything else, is being grossly violated), we should have our Nuclear Experts work on a new, improved, and modernized Treaty that can last long into the future.”
The Axios news service reported that negotiations had been taking place over the past 24 hours in Abu Dhabi and the two countries were closing in on a deal to keep observing key terms of the treaty.
Under New Start, agreed in 2010, both sides agreed to deploy no more than 1,550 strategic nuclear warheads on no more than 700 bombers or missiles.
The expiry of the treaty would leave both countries for the first time in half a century without any legal framework restraining their nuclear ambitions.
