LOS ANGELES, Aug. 24 (Xinhua) -- U.S. Vice President JD Vance said Sunday that Russia has made "significant concessions" in talks aimed at ending its war with Ukraine.

In an interview with NBC News, Vance rejected the notion that Moscow was stringing President Donald Trump along, saying the Russians have been "flexible" on some of their demands.

"I think the Russians have made significant concessions to President Trump for the first time in three and a half years of this conflict," Vance said. "They've actually been willing to be flexible on some of their core demands. They've talked about what would be necessary to end the war."

"Of course, they haven't been completely there yet, or the war would be over. But we're engaging in this diplomatic process in good faith," he added.

"We're going to keep on doing what we have to do to bring this thing to a close," Vance said. "I don't think it's going to happen overnight."

Russian Foreign Minister Sergei Lavrov said Friday that a meeting between Russian President Vladimir Putin and Ukrainian President Volodymyr Zelensky is not being planned.

Intense diplomatic efforts have been underway in recent weeks to end the conflict in Ukraine. Following the Trump-Putin meeting in the U.S. state of Alaska, Trump held talks with Zelensky and European leaders on Monday.