Russia and Ukraine made a long-awaited swap of 70 prisoners on Saturday, a deal hailed as a first step towards ending five years of tensions and conflict.
Two planes carrying 35 prisoners from each side landed simultaneously in Moscow and Kiev, where the passengers emerged under sunny skies.
"We have taken the first step," Ukrainian President Volodymyr Zelensky said on the tarmac after greeting and hugging former detainees. "We have to take all the steps to finish this horrible war."
In emotional scenes at Kiev's Boryspil airport, family members embraced and handed flowers to the former prisoners, many weeping with joy.
Among those swapped were 24 Ukrainian sailors, Ukrainian filmmaker Oleg Sentsov and Russian-Ukrainian journalist Kyrylo Vyshynsky.
"I am overflowing with happiness," Natalya Mokryak, the mother of one of the sailors, told AFP at the airport. "I have finally seen this come true."
Russian state television showed the Russian prisoners emerging from the plane at Moscow's Vnukovo-2 airport used for government flights.
Among those handed over to Moscow was Vladimir Tsemakh -- a fighter with Moscow-backed separatists considered a key witness in the downing of flight MH17 -- who was returned home despite pleas from the Netherlands.
Western leaders welcomed the exchange, with US President Donald Trump saying it could be "a first giant step to peace" and German Chancellor Angela Merkel calling it a "sign of hope".
French President Emmanuel Macron hailed the release of Sentsov in particular, saying in a tweet that "we have always been by his side".
Anticipation had been building for the swap, which involved weeks of behind-the-scenes negotiations.
Relations between Kiev and Moscow nose-dived in 2014 when Russia annexed Crimea and Moscow backed separatists in the eastern industrial regions of Donetsk and Lugansk. Fighting there has claimed more than 13,000 lives over the past five years.
- Smiles and tears -
Zelensky's election in April has raised hopes that a stalled peace process could be revived.
The comedian-turned-politician vowed to have Ukrainian prisoners in Russia returned and has said that ending the conflict with Russia is his top priority.
Russian President Vladimir Putin said this week that the exchange would be "a huge step towards normalising relations" with Kiev.
Saturday's swap was "very important", Russian foreign ministry spokeswoman Maria Zakharova said.
"It's necessary to maintain this drive to solve problems as much as possible," she said.
The release of filmmaker Sentsov will be seen as a major victory for Kiev. The 43-year-old was Ukraine's most famous political prisoner and the subject of a star-studded international campaign calling for his release.
He was arrested in 2014 and had been serving a 20-year sentence in an Arctic penal colony for planning "terrorist attacks" in Crimea.
"I thank all the people who have fought for us," Sentsov said at the airport in Kiev, where he was greeted by his teenage daughter who wept and smiled.
"I am hoping that the rest of the prisoners will be released soon," he added.
The sailors, including two members of Ukraine's SBU security services, were detained last year when Russia seized three Ukrainian vessels off Crimea.
Moscow had wanted to put them on trial for violating Russia's maritime borders.
The commander of the Ukrainian Navy, Admiral Igor Voronchenko, broke into tears as he embraced one of the freed sailors.
- MH17 witness handed over -
Among those who flew to Russia was Vyshynsky, a 52-year-old journalist at Russia's RIA Novosti state news agency.
The Russian-Ukrainian dual national was facing charges of "high treason" but was released on bail ahead of the swap.
The release of Tsemakh -- who was reportedly in charge of air defence in the area where the MH17 came down -- was a demand by Russia for the swap to go ahead, said Ivan Bakanov, the head of Ukraine's SBU.
The Dutch government contacted Ukraine "several times and at the very highest level" to try to prevent Tsemakh's handover, Foreign Minister Stef Blok said.
Blok said the authorities had the opportunity to question Tsemakh before he left for Russia but the Netherlands still profoundly regretted the outcome.
Flight MH17 from Amsterdam to Kuala Lumpur was shot down by a Russian-made missile in July 2014 over eastern Ukraine, killing all 283 passengers and 15 crew on board, two-thirds of them Dutch.
Efforts have intensified to ease tensions between Moscow and Kiev since Zelensky's election, with Macron calling for a summit of the leaders of Ukraine, Russia, France and Germany this month.