Simferopol, Ukraine (CNN) -- Traveling to Crimea? Don't try landing in Simferopol unless your plane originated in Moscow. Flights from Kiev and Istanbul, and several other cities, have been suspended for the rest of the week.
If you come by train, expect to be searched by pro-Russian militia. If you want to rally in favor of Ukraine's West-leaning interim government, expect to be surrounded by pushy pro-Russians.
Breakneck preparations are under way for a referendum on Sunday -- to be held largely in secret -- and the grip of security measures is tightening around Simferopol.
When Crimeans go to vote, they will have choose between two alternatives: Remain an autonomous state within Ukraine, or join the Russian Federation.
But in light of recent developments, the referendum would seem like an afterthought for what is a steadily approaching reality.
The new pro-Russian government on the peninsula in Ukraine's southeast said Tuesday that if the voters opt to join Russia, the first step will be to declare Crimea an independent and sovereign state, governed as a republic. Then it will apply to join the Russian Federation.
Crimea's representatives have already approached Moscow with their idea of joining, and Russian leaders have greeted them with open arms.
Russian-speaking troops wearing no identifying insignia have Crimea firmly under their control. Many believe that they belong at least in part to Russia's military, something Moscow has adamantly denied.
The well-armed men have effectively isolated the peninsula with an ethnic Russian majority from the rest of Ukraine.
There has been an international outcry over Crimea's apparent rash push toward Russian annexation, and warnings that the referendum won't be recognized.
Ukraine's interim government, backed by the United States and European powers, has called it illegitimate.
Welcome to Crimea
Passengers disembarking in Simferopol Tuesday saw pro-Russian militiamen wearing red armbands that proclaim their allegiance to "the autonomous republic of Crimea."
The men helped police search arrivals, sometimes shoving them to where they want them to stand.
"We are looking for people who are bringing in weapons. For security. From Ukraine. From Maidan," a guard explained, referring to Keiv's Independence Square, the epicenter of protests that toppled Viktor Yanukovych, the pro-Russian former president of Ukraine.
A saleswoman offered new cell phone cards to new arrivals -- also for security reasons, she explained.
"The fascist who wants to be president, he wants to bring his armed men here from Kiev, to disrupt our referendum. He doesn't want to negotiate, he just wants to shoot," she said.
A passenger arriving from Russia at the airport seemed confident about how the vote will go.
"Crimea is Russia!" he exclaimed, as he exited.
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Assuming the referendum goes in favor of joining the Russian Federation, the newly installed parliament will place the request to join with Moscow.
The parliament there has announced it will then debate whether or not to accept Crimea.
Yanukovych will be waiting there for it.
He insists he is still the legitimate leader of Ukraine and has vowed to return to Kiev "as soon as the circumstances allow."
Speaking in Rostov-on-Don in southwestern Russia on Tuesday, Yanukovych slammed the interim government in Kiev as "a gang of ultranationalists and fascists."
Yanukovych fled Kiev on February 22, after three months of protests against his decision to scrap a trade deal with the European Union and embrace closer ties with Russia.
Less than a week later, armed men seized the Crimean parliament building in Simferopol and raised the Russian flag above it.
The peninsula in the Black Sea, with a population of just over 2 million people, has stepped into the spotlight of the world stage.
The West has been preparing sanctions and at the same time telling Moscow that there is a way out of an economic and diplomatic showdown: Talk to Ukraine's new government and don't intervene militarily.
Moscow has denounced the events that led to Yanukovych's ouster as an illegitimate coup and has refused to recognize the new Ukrainian authorities.
Russian President Vladimir Putin has said his government has the right to protect ethnic Russians living there.
The U.S. House of Representatives Tuesday overwhelmingly approved a resolution condemning Russia for its military intervention in Ukraine and urging economic and other sanctions in response.
In a 402-7 vote, lawmakers approved a nonbinding resolution stating that Russia's action poses a "threat to international peace and security" and calling on Russia to remove "all of its military forces from Ukraine's Crimean peninsula" other than those that are there in accordance with an agreement on operations of Russia's Black Sea fleet.
The resolution urges the Obama administration to band together with European allies to impose visa, financial, trade, and other sanctions on senior Russian Federation officials, majority state-owned banks and commercial organizations.
The foreign ministers of Germany and France protested anew Tuesday against Crimea's referendum.
Tit for tat
On Tuesday, Russian officials compared Crimea's impending departure from Ukraine to Kosovo's secession from Serbia after many years of bloody civil war with its former neighbor.
Western governments recognized the separation over bitter opposition from Serbia and its historical allies in Moscow.
Russia's foreign ministry cited it in a statement as a precedent for the "absolutely legitimate" Crimean vote.
"The Russian Federation will respect the results of the free vote of Crimea's people during the referendum," it said.
In Crimea, pro-Russian forces were in firm control and repeating the Yanukovych's slurs -- that "fascists" had seized power in Kiev.
Ruslan Dudkin, a volunteer at a militia camp in Simferopol, compared the protesters who rallied in Kiev's Maidan Square to "cockroaches."
"The people on the Maidan would soil and sleep and eat in the same place. It was worse than tramps," he said.