MOSCOW — Russia and Ukraine completed a major prisoner exchange Saturday in a move that raised hopes for eased tensions between the two countries, who have been at war since 2014.

Planes landed almost simultaneously in the countries' capitals, each carrying 35 prisoners.

Russian President Vladimir Putin said Thursday that the highly-anticipated swap, which came after lengthy negotiations, would be “a good step” toward the normalization of relations between Moscow and Kiev.

Ukrainian President Volodymyr Zelenskiy was at Boryspil airport Saturday to greet the prisoners as they returned home.

Zelenskiy, who made peace between the two countries one of his key election promises when he ran for office earlier this year, said all steps had to be taken "to finish this horrible war."

"We have made the first step," he added.

Among the Ukrainians freed were 24 sailors who were detained by Russia in the Kerch Strait last November.

Russia accused the sailors of violating its border and kept them in custody for nearly 10 months. Ukraine has insisted that the men should be treated as prisoners of war.

Ukrainian film director Oleg Sentsov was among those freed. His arrest and imprisonment on terrorism charges in Russia has been a rallying cry for the entertainment industry and human rights groups. GLEB GARANICH / Reuters

President Donald Trump offered his approval for the prisoner swap Saturday.

"Very good news, perhaps a first giant step to peace," he said on Twitter. "Congratulations to both countries!"

The exchange comes amid calls from Trump to re-admit Russia to the G-7 after it was kicked out of the group following the annexation of Crimea in 2014.

Five years of war between Ukrainian troops and Russian-backed forces in eastern Ukraine’s Donbass region have killed 13,000 people, despite a ceasefire signed in 2015.

The swap could set the stage for serious talks, even though major differences remain between the two countries.

French President Emmanuel Macron has been pushing for a summit to discuss the issue with Russia, Ukraine, Germany and France.

Russia's foreign ministry called the exchange "a very important step."

"We need to support as much as possible this attitude to solve problems, not to aggravate them. Political will and systematic hard work bear fruit," spokeswoman Maria Zakharova said on Facebook Saturday.

The released prisoners aboard the Russian plane included Kirill Vyshinsky, head of the Russian state news agency RIA-Novosti's Ukraine branch, who had been jailed since 2018 on treason charges.

Rossiya Segodnya news agency director Dmitry Kiselev and Russian-Ukrainian journalist Kirill Vyshinsky were among those arriving at Moscow's Vnukovo airport. VASILY MAXIMOV / AFP - Getty Images

They also included Vladimir Tsemakh, who is suspected of involvement in the downing of a Malaysia Airlines flight over eastern Ukraine in 2014, the Dutch government said Saturday.

Dutch prosecutors previously urged Kiev not to allow Tsemakh to travel to Russia, fearing this could jeopardize the investigation into Flight MH17, which was en route from Amsterdam to Kuala Lumpur.

Tatyana Chistikova reported from Moscow, with Yuliya Talmazan and Linda Givetash from London.