Twenty-four sailors were detained and "courts" in Russian-occupied Crimea ruled that they be detained for two months, pending trial.
On Sunday, Russian gunboats opened fire on a Ukrainian naval convoy and rammed a tugboat before seizing it and two Ukrainian gunboats.
Nine more Ukrainian sailors captured during Sunday's confrontation with Russia in a strait next to Crimea have been sent to jail for two months by a Russian court.
The tension between Ukraine and Russia reached a new low this week after the Russian border patrol blocked the route of three Ukrainian military vessels travelling from the Black Sea to the Sea of Azov through the Kerch Strait - the shared internal waters of both states according to their 2003 agreement.
Poland's President Andrzej Duda was more emphatic, declaring that if there was a move to impose "further sanctions against Russia, Poland will join them".
The United States and the European Union have both imposed sanctions on Russia over its conduct towards Ukraine since 2014, when Moscow seized and annexed Ukraine's Crimea peninsula after a pro-Russian leader was toppled in Kiev.
Turkey, as well as the UN General Assembly, viewed the annexation as illegal.
Members of Parliament react as Ukrainian President Petro Poroshenko (top) delivers a speech ahead of a parliamentary vote on imposing martial law in the country, in Kiev, Ukraine, November 26, 2018.
"We had information that after this provocation Russian regular forces could go for more aggressive actions against Ukraine.This is why Ukraine's authorities chose to impose martial law", Parubiy says.
APThe Kremlin said on Wednesday it still expected a meeting between President Vladimir Putin and President Donald Trump to go ahead
"They were fulfilling their military duty".
"It was without doubt a provocation", Putin told a financial forum in Moscow of the incident.
Ukraine will defend itself militarily if it has to against "Russian aggression" along the country's coastline in the sea of Azov, the country's foreign minister has told Sky News.
"I hope they understand that", he said.
The seizure of the ships and the arrest of 24 crew members caused worldwide outcry and condemnation of Moscow's moves, including from US President Donald Trump who suggested that he might cancel his planned meeting with Russia's President Vladimir Putin over the aggression.
But the bloc's top powers Germany and France have so far put emphasis on seeking to calm tensions.
The US State Department on Tuesday termed Russia's actions "a unsafe escalation" and said Washington wants to see "our European allies doing more to assist Ukraine". But for now the unity of the 28 is key.
Deployment of S-400 missiles in Crimea?
Mattis made his comments on Ukraine to reporters following remarks to a closed-door Senate session on a proposed resolution that would cut off USA support for Saudi Arabia in Yemen's civil war.
Ukraine-Russia sea clash
Meanwhile, the Kremlin warned Tuesday the declaration of martial law might trigger a flare-up of hostilities in eastern Ukraine. In response to the Kerch Strait incident, Poroshenko wants to impose martial law in Ukraine for the next 30 days.
Nintendo Switch, Red Dead 2, More In Walmart Cyber Monday Gaming Deals
With most of the madness of Black Friday 2018 now behind us, it's finally time for Cyber Monday 2018 discounts to shine. ET, no big US chain had seen any technical difficulties, according to website outage tracker DownDetector.com.
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I don't think it was my best showing, but I got in shape. "I don't know what I'm going to do". It was a result for which Ortiz, 43, had waited years.