Martial law has been declared in Ukraine – proposed by President Petro Poroshenko and approved by parliament earlier this week. The decision comes after Russian forces on November 25 seized three Ukrainian navy vessels and their crew in the Black Sea.

The incident has been described as the most serious maritime clash between the two countries since Moscow annexed Crimea in 2014.

As reported by The Financial Times, the conflict between Russian-backed separatists and Ukrainian forces in the east of the country has claimed more than 10,300 lives.

According to Poroshenko, the naval action was “direct Russian aggression”. But the decision to send the Ukrainian navy ships through the Kerch Strait promoted suggestions from Moscow that Kiev was seeking to exploit the tensions and make use of exceptional powers ahead of presidential elections in March, where Poroshenko seems to be heading for defeat.

Ukraine’s parliament authorised martial law for 30 days. It can be applied selectively to regions bordering Russia, Crimea and its coastal waters and neighbouring Transnistria, a breakaway region of Moldova, where Russia has stationed peacekeeping troops for more than two decades, reported The Financial Times.

“It’s not necessary to be James Bond, a super-intelligence agent, to understand that Russia has plans for… the entire coast,” Ukraine’s foreign minister Pavlo Klimkin warned. He also said Ukraine would sue Russia for damages over violations of maritime rights, part of a long-term strategy by Kiev and its western allies to increase the cost to the Kremlin of Russia’s actions.

“Martial law does not mean the declaration of war,” Poroshenko said on November 26. “It is introduced solely for the purpose of strengthening Ukraine’s defence against the background of growing aggressiveness from Russia.”

According to The Financial Times, the timing has fuelled speculation that Kiev is seeking to draw international attention to the smouldering conflict. It comes days before the G20 summit in Argentina, where US president Donald Trump and Russian president Vladimir Putin are expected to meet. EU leaders meanwhile are scheduled to renew their rolling sanctions on Russia.

According to Brian Mefford, a US political consultant based in Kiev, a period of martial law could help Poroshenko “unite the country, show patriotic resolve in the face of Russian aggression and demonstrate his commitment to hold the election next year”.