Three Ukrainian ships were returned on Monday almost a year after the Russian navy seized the vessels in the Kerch Strait.

Ukrainian officials confirmed the return, a day after tug boats were seen towing the vessels through the strait that separates Crimea from the Russian mainland. Russia's Ministry of Foreign Affairs previously announced the handover earlier on Monday.

The move was "in accordance with the agreements reached with the Ukrainian side," sources from Russian intelligence agency FSB's Crimean branch told Russian news agency Interfax.

The news comes ahead of a crucial summit between the leaders of Ukraine and Russia. The handover is seen as an important step in resolving the ongoing five-year conflict in eastern Ukraine.

What happened in Kerch Strait?

Russia's military had captured one tugboat and two small artillery vessels last November after the Ukrainian crews tried to gain access to the Sea of Azov through the Kerch Strait. The strait is the only naval access point to two of Ukraine's biggest ports, Mariupol and Berdyansk.

Russia accused the Ukrainian navy of trying to stage a "provocation" and illegally entering Russian territorial waters, while Ukraine describes the incident as an act of Russian aggression.

Read more: What you need to know about the conflict in the Sea of Azov

Russian troops opened fire during the incident and one of their vessels rammed a Ukrainian boat. Several Ukrainian crew members were injured. Russian authorities eventually arrested all 24 sailors and later put them on trial for "illegally crossing the border."

What happened to the sailors?

A United Nations tribunal ruled in May that Russia must release the sailors and ships.

The sailors were freed after 10 months in a landmark prisoner swap this September, which also saw Russia sending filmmaker Oleg Sentsov back to Ukraine. However, the legal case against the Ukrainian sailors remains ongoing in Russia.

"After the return of the detained sailors and their ships to Ukraine, ending the case against the sailors should be a natural and reasonable ending for this entire story in Russia," the head of their legal team, Nikolai Polozov, said on his Facebook page.

Will the return of the ships build trust between Russia and Ukraine?

The return of the ships should serve as another trust-building measure between Moscow and Kyiv, as Ukrainian President Volodymyr Zelenskiy pushes for a top-level meeting in the so-called Normandy format, with the presence of France's Emmanuel Macron and Germany's Angela Merkel.

These will be the highest-level talks carried out since 2016.

While the relationship between Moscow and Kyiv remains tense, Zelenskiy's unexpected victory this April signaled a change in the long-running conflict.

ed, dj/bk (dpa, Interfax, Reuters, Ukrainski Novini)

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