At least that’s what Sky News is reporting based on reports from Interfax, although there hasn’t been any other headlines on this yet (Huffington Post UK also has this, but it appears to be from the same source) (Update: BBC also now reporting ultimatum). Ukrainian forces in Crimea have not opened hostilities on Russian occupiers, but they have also refused to surrender their bases on the peninsula. The Russian navy sent an ultimatum for a surrender, or “a real assault” will commence shortly:

The ultimatum, from the commander of Russia’s Black Sea Fleet Alexander Vitko, has a base in Crimea where Russian forces are now in control.

According to the agency, it reads: “If they do not surrender before 5am (3am GMT) tomorrow, a real assault will be started against units and divisions of the armed forces across Crimea.”

The Russians must be surprised that Ukraine has not fought back yet — and a little frustrated, too. In 2008, Vladimir Putin baited Georgia president Mikhail Saakashvili into military action as two provinces with large ethnic-Russian populations threatened to break away. Russia invaded Georgia on that pretext, and still control South Ossetia and Abkhazia. The new leaders of Ukraine clearly have Georgia on their mind as they insist that their mobilization is not intended for anything but defense of ground already controlled by Ukraine, and not a liberation of Crimea. Instead, they want the West to come to their aid politically and economically, rather than militarily:

ABC Entertainment News | ABC Business News

Over the past few days, highly-organized and heavily-armed troops believed to be Russians – but bearing no identifying patches – have encircled Ukrainian bases, demanding they surrender.

The deputy commander of a naval operations base in the Crimean capital Simferopol told ABC News on Sunday that Russian forces had twice asked he and his men to leave but so far they have refused. His orders were to stand firm, he said, adding that they have weapons and are ready to fight.

But there have been no clashes so far, Russia managing to take control of Crimea without firing a shot. The airports, parliament and other government buildings are under the control of the militias.

So far, Ukraine’s new government and the West have appeared powerless to counter Russia’s tactics. Ukrainian Prime Minister Arseniy Yatsenyuk insisted that Crimea remains Ukrainian territory despite the presence of Russian military.

“Any attempt of Russia to grab Crimea will have no success at all. Give us some time,” he said at a news conference with British Foreign Secretary William Hague, who is visiting Kiev.

“For today, no military options (are) on the table,” he said, adding that what they urgently need is an economic and political support.

The military option may be what’s on Russia’s table, though. They seem to be itching for a fight as a pretext for wider action, and are probably eyeballing eastern Ukraine as well. Ukraine’s full mobilization will only hold off Russia for a short time, and Yatsenyuk clearly wants to prevent Russia from seizing any more ground by improving readiness but remaining as still as possible otherwise.

It’s difficult to see how this ends well. Russia’s invasion of Crimea was based on a non-existent pretext of oppression of ethnic Russians, so it’s unclear that they’ll simply stall for a real provocation. At some point, they’ll just make one up. Still, this is really Yatsenyuk’s only play, especially since he’s not going to get military assistance from Europe.