The American defense secretary, Lloyd Austin, has spoken to his Russian counterpart about the destruction of an American drone over the Black Sea after an encounter with Russian fighter jets, which brought the two countries closest to direct conflict since Moscow’s invasion of Ukraine a year ago.

Wednesday’s call was the first between Mr. Austin and the Russian defense chief, Sergei Shoigu, since October. Also, the chairman of the Joint Chiefs of Staff, General Mark Milley, had a similar call with his Russian counterpart, Valery Gerasimov, the chief of the general staff of the Russian armed forces.

“We take any potential for escalation very seriously. And that’s why I believe it’s important to keep the lines of communication open,” Mr. Austin said at a Pentagon press briefing. “I think it’s really key that we’re able to pick up the phone and engage each other. And I think that that will help to prevent miscalculation going forward.”

The military said it ditched the Air Force MQ-9 Reaper in the sea after a Russian fighter jet poured fuel on the surveillance drone and then struck its propeller while it was flying in international airspace. Russia has denied that it caused the accident. The Pentagon early Thursday released surveillance footage from the drone that showed Tuesday’s incident.

That the top American and Russian defense and military leaders were talking so soon after it occurred underscored the seriousness of the encounter over the Black Sea and that both sides recognized the need to tamp down the risks of escalation. Since Russia’s invasion of Ukraine, contact between American and Russian military leaders has been limited, with Russian officials refusing to take American military calls in the early months of the war.

There are still questions as to whether Russia meant to down the drone, even though the moments that led up to its crash were “intentional,” General Milley, who stood alongside Mr. Austin at the briefing, said.

“We know that the intercept was intentional. We know that the aggressive behavior was intentional,” General Milley said. However, he told reporters that it was still unclear whether the collision itself was intentional. 

Also, he pushed back against Russia’s contention that the fighter jets did not come in contact with the drone. “We have absolute evidence of the contact,” General Milley said. “It’s very aggressive. … We have video evidence and all that.”

General Milley and Mr. Austin also left open the possibility that America could try to recover portions of the downed $32 million drone, which Mr. Milley said crashed into waters that were 4,000 to 5,000 feet deep. 

Other American officials said that the United States  doesn’t have military ships in the region, and won’t likely seek to recover wreckage. The Black Sea has been closed since early 2022 to military vessels that do not have a home port along its shores.

The officials, who spoke on the condition of anonymity to provide details not yet made public, said Russia has already sent ships to the area and attempted to recover pieces of the drone.

General Milley downplayed the significance of any potential recovery by Russia. “It probably broke up. There’s probably not a lot to recover,” he said. “As far as the loss of anything of sensitive intelligence, etc. … we would take — and we did take — mitigating measures. So we’re quite confident that whatever was of value is no longer of value.”

Officials have long acknowledged that sensitive information can be removed from high-tech drones and systems made inoperable so they aren’t of much value.

Details of General Milley’s call with Mr. Gerasimov would be kept private, the Joint Staff spokesman, Colonel Dave Butler, said in a statement. Mr. Gerasimov was named the new commander of the Russian forces in Ukraine in January and its previous commander demoted in an apparent sign of the Russian president’s dissatisfaction with the state of the war, which has been stalemated.

If the call between Messrs. Austin and Shoigu was de-escalatory in private, it was not apparent from Russia’s public statements.

Russia’s foreign minister, Sergei Lavrov, told reporters earlier Wednesday that Russia has declared certain areas of the Black Sea off-limits to any aerial traffic during the conflict and suggested that Washington was trying to provoke an escalation through the flights. The drone crashed near Ukraine’s Crimean peninsula, which Russia seized in 2014 and illegally annexed.

“Any incidents that could provoke confrontation between the two great powers, the two largest nuclear powers, raise very serious risks,” Mr. Lavrov said.

The Russian defense ministry said Mr. Shoigu, in the call with Mr. Austin, noted that the flights of American drones near Crimea were “provocative” and risked escalating tensions in the Black Sea. He said Russia would respond “in kind to all provocations” in the future, but also noted that the two nuclear powers must act responsibly and maintain channels of communication.

Asked about the call, Mr. Austin declined to provide any details. He first spoke with Mr. Shoigu about Russia’s invasion of Ukraine in May 2022. At the time it was the highest level American-Russian contact of the war.