Poroshenko said martial law was necessary to bolster Ukraine’s defenses after Russia seized three Ukrainian naval ships and took their crew prisoner at the weekend.
US President Donald Trump said he did not like what was happening between Russia and Ukraine and was working with European leaders on the situation.
US Secretary of State Mike Pompeo called Russia’s seizure of the Ukrainian vessels “a dangerous escalation and a violation of international law” and called for restraint from both countries.
“The United States condemns this aggressive Russian action. We call on Russia to return to Ukraine its vessels and detained crew members, and to respect Ukraine’s sovereignty and territorial integrity,” Pompeo said in a statement.
The State Department said Pompeo spoke by phone with Poroshenko and reiterated strong U.S. support for Ukraine’s sovereignty and territorial integrity in the face of Russian “aggression”.
The Ukrainian parliament approved the introduction of martial law after Poroshenko reassured some skeptical lawmakers that it would not be used to curb civil liberties or delay elections scheduled for next year.
It came at the end of a day when Ukraine and Russia traded accusations about Sunday’s standoff and Kiev’s allies weighed in to condemn Moscow’s behavior.
With relations still raw after Russia’s 2014 annexation of Crimea from Ukraine and its backing for a pro-Moscow insurgency in eastern Ukraine, the crisis risked pushing the two countries into open conflict.
“Russia has been waging a hybrid war against our country for a fifth year. But with an attack on Ukrainian military boats it moved to a new stage of aggression,” Poroshenko said.
In a phone call with Poroshenko, NATO Secretary General Jens Stoltenberg offered the alliance’s “full support for Ukraine’s territorial integrity and sovereignty.” Ukraine is not a NATO member though it aspires to membership.
Washington’s envoy to the United Nations, Nikki Haley, said Russia’s actions were an “outrageous violation of sovereign Ukrainian territory” and sanctions on Russia would remain in place.
The European Union, Britain, France, Poland, Denmark, and Canada all condemned what they called Russian aggression. German Chancellor Angela Merkel stressed the need for dialogue.
The stand-off in the Azov Sea is more combustible now than at any time in the past four years as Ukraine has rebuilt its armed forces, previously in disarray, and has a new generation of commanders who are confident and have a point to prove