Ukrainian President Petro Poroshenko signed a decree on Monday to introduce martial law for 60 days, a statement on his website said, though it needs parliamentary approval to come into force.
The decision came a day after Russia fired at and captured three Ukrainian vessels, triggering a sharp escalation in tensions between the two countries.
Parliament was expected to debate the decree later on Monday though a televised session of a parliamentary committee unanimously supported it.
A Ukrainian diplomat was seen entering the Russian foreign ministry on Monday, RIA news agency reported, hours after Moscow promised to summon a Ukrainian representative to discuss an incident in the Kerch Strait on Sunday.Russia seized two small Ukrainian armoured artillery vessels and a tug boat, which Moscow said had illegally entered Russia's territorial waters. Kiev said its vessels did nothing wrong and has accused Russia of military aggression. Video: Three Ukrainian ships seized by Russia are moored at Crimean port of Kerch
Russia summons Ukrainian diplomat over Kerch Strait incident
Ukrainian legislation on martial law allows for a slew of curbs, including restrictions on movement and peaceful assembly, curfews, and restricting the media, though Poroshenko's decree made no specific references to such restrictions.
Eleven measures outlined in the decree provide for mobilizing reserve forces, organizing the air defence of important state facilities and taking urgent steps to bring in enhanced cyber security measures and ensure public order.
There was no mention of a presidential election due to be held in March. Poroshenko's move has prompted speculation by critics and opposition politicians that he might use it to delay the vote.
A twelfth provision of the decree was not published.
At the request of Ukrainian President Petro Poroshenko, NATO Secretary General Jens Stoltenberg agreed to convene an extraordinary meeting of the NATO-Ukraine Commission (NUC) at an Ambassadorial level in Brussels on Monday afternoon to discuss developments in the Azov Sea and Kerch Strait.During a phone call with Poroshenko, Stoltenberg discussed the current situation with the Ukrainian president and expressed NATO’s full support for Ukraine’s territorial integrity and sovereignty, including its full navigational rights in its territorial waters under international law. The crisis began on Sunday after Russia stopped the three Ukrainian ships from entering the Sea of Azov by placing a cargo ship beneath the bridge. Ukraine said a Russian ship had earlier rammed its tug boat in a failed to attempt to stop it.Russia reopened the Kerch Strait near Crimea to shipping in the early hours of Monday.The developments have triggered a dangerous new crisis between the two countries.Video: Three Ukrainian ships seized by Russia are moored at Crimean port of KerchEU's Tusk says Europe will stay united in support of UkraineUkraine's Azov Sea ports operating normally despite tensions with RussiaRussia reopens Kerch Strait to shipping after standoff with UkraineTurkey says Kerch Strait must remain open after Russia-Ukraine standoff
Poroshenko, Stoltenberg convene emergency NATO-Ukraine Commission meeting
European Council President Donald Tusk on Monday condemned Russia's seizure of Ukrainian navy vessels in the Kerch Strait."I condemn Russian use of force in the Azov Sea. Russian authorities must return Ukrainian sailors, vessels and refrain from further provocations," Tusk said after a phone call with Ukrainian President Petro Poroshenko."Europe will stay united in support of Ukraine."Video: Three Ukrainian ships seized by Russia are moored at Crimean port of Kerch
EU's Tusk says Europe will stay united in support of Ukraine