Russian President Vladimir Putin and Ukraine's new president Volodymyr Zelensky discussed the conflict in eastern Ukraine in their first telephone conversation, the Kremlin said Thursday, July 11, AFP reports.

Zelensky's office said the release of 24 Ukrainian sailors held by Russia since November was a "key question" during the call. Russia seized their vessels off Crimea last year.

"Questions of regulating (the conflict) in south-east Ukraine and joint work on the return of persons held on both sides was discussed," Putin's spokesman Dmitry Peskov told Russian news agencies after Putin's first contact with Zelensky, who was inaugurated in May.

"The return of other Ukrainian citizens held on Russian territory" was also discussed, the statement on the website of the Ukrainian presidency added.

Earlier this week Zelensky called for first talks with Putin in a video address, calling for Western leaders to mediate.

He suggested that the US and Britain should also be included in peace talks on the conflict that currently involves Germany, France, Russia and Ukraine.

Putin on Thursday said Moscow "never refused any of the proposed formats", including the expansion of the group, Russian media reported.