A decree by President Petro Poroshenko to impose martial law on his country was approved 276-30 by Ukrainian lawmakers on Monday, while the US had severe words for Moscow at the UN, after Russian forces seized three Ukrainian naval vessels and their crews near the disputed Crimea region the day before.

At an emergency meeting of the UN Security Council, US ambassador Nikki Haley warned Russia that its action in seizing the ships was an "outrageous violation of sovereign Ukrainian territory."

She said her statement reflected "the concerns at the highest level" of US leadership, adding that "outlaw actions like this one" would make it impossible for the US to normalize relations with Russia. The US stopped short of calling for further sanctions against Russia.

Russia's deputy UN ambassador, Dmitry Polyanskiy, in his turn accused Ukraine of planning the incident as a way of boosting Poroshenko's popularity ahead of an election in March.

Several European nations, including Germany, France and Britain, issued a statement following the meeting that called for restraint and de-escalation, as well as reaffirmed recognition of Ukraine's territorial integrity.

Martial law proposal

The Ukrainian president had earlier announced that he had signed a bill calling for martial law in response to the incident.  

Martial law would mean, among other things, partial mobilization of the country's military and stepping up air defense — moves that raise fears of a military escalation in the region.

In a televised address, Poroshenko said he had reduced his original call for two months of martial law to 30 days from November 28. The reduction was made in apparent response to opponents who said his initial proposal for 60 days would prevent elections scheduled for March going ahead as expected.

The Ukrainian navy says six of its seamen were injured in the Russian action, during which Russian border guards opened fire on the vessels in the Kerch Strait, a waterway between Russian-annexed Crimea and mainland Russia that flows between the Black Sea and the Sea of Azov.

Read more: Do sanctions against Russia work? 

Fraught waterway

The Kerch Strait and the Sea of Azov are designated as shared territorial waters by a 2003 treaty, but Russia has asserted more control over the waterways since it annexed Crimea in 2014 in a move that drew widespread condemnation and international sanctions.

In recent weeks, Russia has increased its military presence in the area and started inspecting all vessels traveling to or from Ukrainian ports, causing lengthy delays and disrupting trade. 

Ukraine had previously detained a Russian fishing vessel travelling from Crimea in March.

Read more: The Odessa massacre: Remembering the 'Holocaust by bullets'

<div class="opinary-widget-embed" data-poll="do-you-think-russias-recent-actions-cons" data-customer="deutschewelleeng"></div> <script async type="text/javascript" src="//widgets.opinary.com/embed.js"></script>Prisoners of war?

In the latest incident, both sides have traded accusations of the other's being in breach of international norms, with Moscow saying Kyiv failed to obtain authorization for the passage of its vessels, and Kyiv claiming Moscow had ignored a notification sent by the ships.

Ukrainian Foreign Minister Pavlo Klimkin said on Monday that the captured seamen should be treated as prisoners of war. Kremlin spokesman Dmitry Peskov has so far not said whether Moscow will accord them that status.

Tensions between the former Soviet republic of Ukraine and Russia have been growing since 2013, when large-scale protests led to the ousting of pro-Kremlin President Viktor Yanukovych. The Russian annexation of Crimea in 2014 and a Moscow-backed insurgency in Ukraine's east have further fanned the flames.

tj/msh (AP, dpa)

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