U.S. Special Representative for Ukraine Negotiations Ambassador Kurt Volker says that the United States hopes that Russia will release captive Ukrainian sailors "as expeditiously as possible, ideally before Christmas."

"I think they should [release captive Ukrainian sailors], and all of us are urging to do so, so it should be a goodwill gesture. And if so, I hope that we were able to build on that, we can get some momentum," he told the TSN television news service in an exclusive interview. "We hope that is done as expeditiously as possible if they insist on it but the important thing is just to release the sailors as soon as possible, and ideally before Christmas."

At the same time, Volker did not mention which Christmas he meant, as starting from 2018, Ukraine also celebrates Christmas according to the Gregorian calendar, on December 25. Ukrainians will also continue marking this holiday according to the Julian calendar, on January 7.

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Volker mentioned a recent conversation between Russian President Vladimir Putin and German Chancellor Angela Merkel. The former says that the Ukrainian sailors are being tried in Russia, and any discussion of their swap for Russian citizens convicted in Ukraine is possible after the trial is over.

"As of now that's not what the Russians have said. Most recently, I believe President Putin and Chancellor Merkel had a conversation in which he referred to a so-called 'legal' process within Russia. It's obviously not legal but nonetheless he referred to a legal process they had to go through," Volker said.

On November 25, Russia blocked the passage to the Kerch Strait for the Ukrainian tugboat "Yany Kapu" and two armored naval boats "Berdyansk" and "Nikopol," which were on a scheduled re-deployment from the Black Sea port of Odesa to the Azov Sea port of Mariupol. The Ukraine Navy Command noted that the Russian side had been informed of the plans to re-deploy the vessels in advance in accordance with international standards to ensure the safety of navigation. The Russian coast guard ship "Don" rammed the Ukrainian tugboat, damaging the Ukrainian vessel. As the Ukrainian boats were heading back in the Odesa direction after being rejected passage via the Kerch Strait, Russian coast guards opened aimed fire on them. All 24 crew members on board were captured and later remanded in custody for two months, being charged with "illegal border crossing" (the sailors are facing up to six years in prison). Three crewmen were wounded in the attack. Russian-controlled "courts" in occupied Crimea ruled that all 24 detainees should be remanded in custody, after which they were transferred to the Moscow-based Lefortovo and Matrosskaya Tishina detention centers.