Kiev, Ukraine – A 30-day period of martial law has taken effect in 10 of Ukraine’s 27 regions on Wednesday, with President Petro Poroshenko saying it aims to prevent an all-out Russian invasion.
The measure, which affects the regions closest to Russia’s military bases – the first ever martial law in the country’s history – was approved by parliament on Monday, a day after a clash between Ukrainian and Russian forces in the Sea of Azov.
The largely symbolic legislation was activated after Poroshenko and Andriy Parubiy, chairman of Verkhovna Rada – the Ukrainian parliament – signed and published it in the government newspaper, Uryadovy Courier.
The Kremlin has condemned the development, saying martial law will escalate the conflict that saw Moscow seize three Ukrainian ships and capture 24 crew members off the coast of the Russian-annexed Crimean peninsula.
On Wednesday, Russia’s Southern Military District spokesperson, Vadim Astafyev, told Interfax news agency that a fourth S400 surface-to-air missile battalion would soon be deployed to Crimea.
The annexed peninsula already has three such missile installations, which are capable of shooting down up to 36 aircraft at a range of 400km. The new missiles will be operational by the end of the year, according to Russia’s Ria news agency.
Ukraine has yet to comment on the development.
Volodymyr Fesenko, director of the Penta centre for political studies, told Al Jazeera martial law was “for now more like a preventive measure”.
But in case of any “manifestations of the Russian aggression”, Ukraine would be able to respond militarily, he said.
“It will not affect the day-to-day life of ordinary people,” said Fesenko.
Poroshenko, who critics allege initiated martial law to postpone Ukraine’s March 31 presidential elections, said on a local TV station on Tuesday that Kiev had to resort to it to save the country.
“Ukraine is facing a threat of a full-scale war with the Russian Federation,” he said.
Asked why Kiev did not impose martial law when Crimea was annexed by Moscow in 2014 and Russian-backed rebels seized parts of Donetsk and Luhansk regions, Fesenko told Al Jazeera “it was hard to say”.
“At that time, the law enforcement agencies and majority of the government were simply disorganised and demoralised,” he said. “Also, Ukraine’s international partners advised Kiev against it.”
Fesenko rejected the pro-Russian theory that Ukraine may have provoked the latest flare-up to bring the ongoing, Russia-backed, separatist violence in the east back onto the international community’s radar. The fighting has killed more than 10,000 people in the country since 2014.
The Sea of Azov conflict on Sunday that saw Russia temporarily close the Kerch Strait came two months after Poroshenko announced the creation of a new naval base in the area between Crimea and Russia.
He made the move after two Ukrainian warships – the search and rescue ship A500 Donbas and the seagoing tug A830 Korets – on September 23 passed through the strait for the first time without incident. The vessels used to be part of the country’s Black Sea fleet.
The country lost much of its navy after the annexation of Crimea when Russia seized Ukraine’s ships.
The developments of the last few days have affected the Ukrainian currency as markets reacted to the tension.
The hryvnia lost five percent of its value, but the situation is temporary, according to Pavlo Kukhta, deputy chairman of Strategic Advisory Group at the Cabinet of Ministers of Ukraine.
“It is typical for a situation like this. Psychological reactions happen when risks are higher, but it does not really affect the economy in a major way,” he told Al Jazeera.
Kukhta also said since Russia has already reopened the Kerch Strait for commercial shipments, the effect of the conflict is also expected to be limited to the Mariupol region’s port from where Ukraine exports one-quarter of its metals.
Ukraine’s economy suffered a major blow when it lost control over Crimea and parts of Luhansk and Donetsk as many factories are based in the territory. But the country has weathered its worst days, according to Kukhta, with economic growth at an average European rate of 3.5 percent this year.
Follow Al Jazeera’s Tamila Varshalomidze on Twitter: @tamila87v