An emergency meeting of the United Nations Security Council was called for Monday morning over the escalating situation, which would be attended by outgoing U.S. Ambassador Nikki Haley.
Armed Russian warplanes also simulated an attack on a Belgian frigate taking part in North Atlantic Treaty Organisation policing in the Baltic Sea last Thursday, the Belgian military said on Sunday. Ukraine's parliament will hold an emergency session on Monday at 4pm in Kiev to discuss whether to impose martial law.
The incidents were followed by protests outside the Russian embassy in the Ukrainian capital Kiev, which saw activists placing paper boats on the steps of the building and setting off smoke bombs.
Russian Federation illegally claims the waterway as its own, denying Ukraine access to its Azov ports from the Black Sea.
"We need new sanctions against Russian Federation".
The Russian government is accusing Ukraine of a deliberate provocation, while Ukraine says it was "an act of aggression".
Moscow will summon a senior Ukrainian diplomat to complain about the incident, foreign ministry spokeswoman Maria Zakharova said on state television.
Recall, there is a fight, shooting: Ukrainian ships were subjected to a massive attack.
But Ukraine said it had informed the Russians of its plan to move its ships through the sea to Mariupol.
It also said the Kerch Strait was blocked by a tanker, and that Russian military aircraft were flying over the area.
According to the BBC, Ukraine alleges Russian special forces captured two of its gunboats and a tug after a chase.
The three injured sailors are receiving medical treatment and their lives are not in danger, the FSB said.
"What is happening now at the (Kerch) bridge threatens to turn into a very unpleasant story", Kiselyov said.
The Russian ruble opened 0.4 per cent weaker against the dollar in Moscow, its lowest since mid-November.
In recent months both sides had deployed more naval and border vessels to the area.
Kiev insists the two small Ukrainian armoured artillery vessels and a tug boat, heading to Ukrainian ports in the Sea of Azov, were observing worldwide maritime rules.
Mariupol is close to the region controlled by Russian-backed separatists in a conflict that has caused at least 10,000 deaths since 2014.
European Union foreign ministers will discuss a range of issues in Brussels on Monday (19 November), including for the first time the militarisation of the Azov Sea, which according to diplomats has been effectively blockaded by Russian Federation.
"Following the decision of the National Security and Defence Council of Ukraine concerning the implementation of the martial law, Chief of General Staff of the Armed Forces of Ukraine has ordered to place the AFU units on full alert", said in a statement of Ministry of Defence of Ukraine.
"We believe that it's wrong and unsafe to solve electoral tasks by waving a flag of war", he said.