Ukraine is pulling its forces out of Crimea in the face of threats and pressure from the Russian military, acting president Oleksander Turchinov said on Monday.
Turchinov, speaking in parliament after Russian troops entered a key Ukrainian marine base near Feodosia crowning a gradual take-over of Ukrainian military facilities on the peninsula, said the decision had been taken in the face of "threats to the lives and health of our service personnel" and their families.
"The National Defence and Security Council has instructed the Defence Ministry to carry out a re-deployment of military units in Crimea and carry out the evacuation of their families," he said.
U.S. President Barack Obama said Monday that Russia must pay a price for its actions in Ukraine.
"Europe and America are united in our support of the Ukrainian government and the Ukrainian people," Obama said, after talks with Dutch Prime Minister Mark Rutte. "We are united in imposing a cost on Russia for its actions so far."
"We both regard Russia's attempts to annex the Crimea as a flagrant breach of international law, and we condemn its actions in the strongest possible terms," Rutte said.
The presence of 53 world leaders at a Nuclear Security Summit in The Hague was an "important opportunity" to discuss developments in Ukraine, he added.
Earlier Monday, Russian troops forced their way into a Ukrainian marine base in the Crimean port city of Feodosia, overrunning one of the few symbols of resistance left after Moscow wrestled the peninsula away from Kiev, defending soldiers inside said.
The Russians used stun grenades and fired automatic weapons as they charged in, a Ukrainian military official said. Ukrainian flags had been taken down from flagpoles inside the base.
Ukrainian army officer, First Lieutenant Anatoly Mozgovoy, told Reuters by phone from inside the compound that the Russians had fired shots and the Ukrainian soldiers were unarmed. Asked if the base had been taken over, he said: "Yes."
"The invading troops were using stun grenades and also firing automatic weapons. The interior of the compound is full of Russian troops," said Vladislav Seleznyov, a Ukrainian military spokesman in Crimea.
Russian forces had already captured part of the base, used by the 1st Separate Marine Battalion, Ukraine's top military unit, earlier this month.
But Ukrainians had previously appeared to be in control of the armoury, the barracks and other facilities in the compound.
Russia's seizure of Crimea, a Black Sea peninsula of two million people with a narrow ethnic Russian majority, has been largely bloodless.
Moscow formally annexed Crimea on March 21 in a move not recognised by Kiev and the West, prompting sanctions on Russia over the Cold War-era style conflict.
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