KYIV, Ukraine -- Ukraine and its Western allies Monday (November 26) demanded the release of three Ukrainian ships fired on and seized by Russia near Crimea.
Russian sailors boarded and captured the ships on Sunday, accusing them of illegally entering Russian waters off the coast of Crimea in the Sea of Azov.
The crisis unfolded as two small Ukrainian warships and a tugboat were heading through the Kerch Strait, a waterway that gives access to the Sea of Azov from the Black Sea and that both Ukraine and Russia use.
Ukraine said a Russian border guard vessel rammed the tugboat and then fired on the ships, immobilising all three. It said the Kerch Strait was blocked by a tanker and that Russian military aircraft were flying over the area.
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".
Ukraine said six of its servicemen were injured, two seriously. The FSB said only three had suffered non-life threatening injuries and received medical treatment.
Russian news agencies quoted port officials in Crimea as saying the strait was reopened to traffic early Monday.
The United Nations (UN) Security Council held an emergency session Monday. NATO also called an emergency meeting on the incident.
"We will demand [at the UN Security Council] the immediate release of our sailors and the liberation of our ships."
Klimkin said talks were under way with the European Union and others on increasing sanctions imposed on Russia.
France called on Russia to release the sailors and ships, with its Foreign Ministry saying "nothing appears to justify the use of force" by Russia.
Britain condemned Russia's "act of aggression" against Ukrainian ships in the Kerch Strait.
German Foreign Minister Heiko Maas said any Russian "blockade" of the Sea of Azov was "unacceptable".
On Monday he proposed that France and Germany mediate the crisis between Moscow and Kyiv.
Martial law under consideration
Tensions have been building over the Kerch Strait, where Russia has built a new bridge that gives it a land connection to Crimea, which Moscow illegally annexed in 2014.
Kyiv has accused Moscow of blocking access for Ukrainian ships though the strait, the only way in and out of the Sea of Azov to the Black Sea.
In recent months both sides had deployed more naval and border vessels to the area.
Ukraine's military was on high alert and parliament was to vote Monday on a request from President Petro Poroshenko to impose martial law for 30 days.
Poroshenko held a late-night meeting of his military cabinet, proposing the imposition of martial law in Ukraine "to ensure the security and safety of its citizens".
Protesters gathered in several Ukrainian cities to denounce Russia's actions, with several hundred far-right activists marching to parliament in Kyiv and setting off flares.
The confrontation is a concerning development in the long-running conflict pitting Ukraine against Moscow and Russian-backed rebels in the east of the country. More than 10,000 people have died in the fighting.