Sunday's incident has sparked global condemnation over Russia's use of force.
Russia and Ukraine have been locked in long-simmering conflict since the annexation of Crimea by Russia in 2014, and a war with Russian-backed separatists in the country's east has claimed more than 10,000 lives. A Russian ship rammed a Ukrainian military tugboat before coast guard vessels opened fire on the two Ukrainian gunships it was accompanying.
Ukraine also received a boost from the global reaction, underscoring both the isolation of Russian Federation from the West over the Ukraine conflict, and the desire to protect the worldwide maritime convention that allows for unimpeded shipping through any strait.
One of the sailors is heard saying "the actions of the Ukrainian armed vessels in the Kerch Strait had a provocatory character" - parroting the version of events put forward by Russian authorities.
Germany, potentially the leading voice in any call for Western action called upon both sides to de-escalate the new tension, while signaling a tougher line towards Russian Federation.
The Ukrainian parliament late on Monday voted in favour of Poroshenko's request for the introduction of martial law in border areas for 30 days.
Calling Russia's capture of Ukrainian seamen "unacceptable", the European Union's foreign policy chief, Federica Mogherini, urged Russia to "immediately release" them and provide them with medical aid.
"There's room to close that gap", Sleboda said, "and a little bit of military patriotic excitement, presenting him as the protector of the country against Russian aggression, is exactly what was called for".
"Poroshenko's decision to impose martial law is a surprising action, one which is inadequate in relation to the current threat", analysts from Centre for Eastern Studies, a think tank in Warsaw, wrote on Monday afternoon before the Rada met to vote on Poroshenko's proposed martial law order.
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The parliament nonetheless watered down Poroshenko's request amid fears that it was an attempt to postpone elections next March in which he is now projected to lose. Ukraine has two big ports on the northern shore of the Azov sea, and a 2003 treaty allows both countries free access to its waters. Ukraine says that three of its ships were travelling from Odessa to Mariupol when they were intercepted by the Russian coast guard.
At a UN Security Council meeting, USA ambassador Nikki Haley urged Moscow to "immediately cease its unlawful conduct" in the Black Sea.
Russia´s FSB security service, which oversees border forces, confirmed weapons had been fired and the vessels seized, accusing the Ukrainian ships of "violating the Russian border".
A video filmed from aboard a Russian vessel shows Russians chasing the Ukrainian tugboat and ramming the vessel.
Russia's acting United Nations ambassador, Dmitry Polyansky, accused the Ukrainian Navy of "staging an aggressive provocation", which he claimed was aimed at drumming up public support for Poroshenko ahead of Ukraine's presidential election in March. The Strait links the Azov Sea to the Black Sea.
In a phone call with German Chancellor Angela Merkel on Tuesday, Putin said he is "seriously concerned" about the weekend's incident.
By mid-afternoon Monday, there had been no response from the White House or the State Department to the crisis, but Haley said she was speaking after consulting with President Donald Trump and Secretary of State Mike Pompeo. "We're all working on it together", Trump told reporters. Dmitry Polyanskiy, Russia's first deputy permanent representative to the United Nations, told the Security Council the incident was another example of Ukrainian leaders trying to provoke Russia for political purposes.
"We do not like what's happening, either way, we don't like what's happening and hopefully it will get straightened out", he said on Monday, days ahead of another meeting with Putin at the G20 summit in Argentina.