Russian President Vladimir Putin asked parliament Saturday for permission to use the country’s military in Ukraine, moving to formalize what Ukrainian officials described as an ongoing deployment of Russian troops in the strategic region of Crimea.

Putin’s motion loosely refers to the “territory of Ukraine” rather than specifically to Crimea, raising the possibility that Moscow could use military force in other Russian-speaking provinces in eastern and southern Ukraine where many oppose the new authorities in Kiev.

US President Barack Obama warned Moscow on Friday “there will be costs” if Russia intervenes militarily.

“I’m submitting a request for using the armed forces of the Russian Federation on the territory of Ukraine pending the normalization of the socio-political situation in that country,” Putin said in a statement released by the Kremlin.

He said the move is needed to protect ethnic Russians and the personnel of a Russian military base in Ukraine’s strategic region of Crimea. Putin sent the request to the Russian legislature’s upper house, which has to approve the motion, according to the constitution. The rubber-stamp parliament is certain to approve it in a vote expected Saturday.

Obama called on Russia to respect the independence and territory of Ukraine and not try to take advantage of its neighbor, which is undergoing political upheaval.

“Any violation of Ukraine’s sovereignty and territorial integrity would be deeply destabilizing,” Obama said in a statement delivered from the White House. Such action by Russia would not serve the interests of the Ukrainian people, Russia or Europe, Obama said, and would represent a “profound interference” in matters he said must be decided by the Ukrainian people.

Ukraine accused Russia on Saturday of sending thousands of extra troops into Crimea, with Defense Minister Igor Tenyukh telling the Ukrainian government’s first cabinet session that Russia’s armed forces had sent in 30 armored personnel carriers and 6,000 additional troops into Crimea in a bid to help local pro-Kremlin militia gain broader independence from the new pro-EU leaders in Kiev.

Tenyukh accused Russia of starting to send in these reinforcements on Friday “without warning or Ukraine’s permission.”

The defense chief spoke as dozens of pro-Russian armed men in full combat gear patrolled outside the seat of power in Crimea’s capital Simferopol, a day after similar gunmen seized control over airports and government buildings in the territory.