BRUSSELS (AP) -- The European Union slapped travel bans and asset freezes Monday on 21 people from Russia and Crimea who they linked to the push for the secession of Ukraine's strategic Black Sea peninsula.
The sanctions came hours after Crimea's parliament declared the region an independent state, following its residents' overwhelming vote Sunday to break away from Ukraine and seek to join Russia.
EU foreign ministers threatened even tougher measures when EU leaders open a two-day summit on Thursday if Russia does not move to ease the crisis.
"We needed to send a clear message and that is what we have done," German Foreign Minister Frank-Walter Steinmeier told reporters in Brussels.
Across the Atlantic, U.S. President Barack Obama froze assets of seven Russian government officials and four Ukrainians.
The EU insisted it wanted to tread carefully to leave open the diplomatic options for Russia to engage in talks with the Ukraine government. It is walking a tightrope between punishing Moscow and keeping open lines of communication in one of the worst crises in years on its eastern doorstep.
In an indication that the sanctions were milder than feared, stock markets rose across Europe, especially in Moscow.
"So far the sanctions seem fairly toothless and much less severe than had been expected last week," said Kathleen Brooks, research director at Forex.com. "The biggest risk was that the referendum would trigger tough sanctions against Russia that could lead to another Cold War." In Moscow, the main RTS index spiked 5 percent.
Steinmeier said the sanctions would hit eight top Crimea politicians, 10 Russians, including members of the duma and the federal council and three Russian military commanders.
The EU has already suspended talks with Russia on a wide-ranging economic pact and a visa agreement. The bloc's leaders are meeting Thursday and Friday and could start slapping economic sanctions on Russia this weekend if Moscow does not back down.
If the crisis escalates further, measures could include freezing assets of Russian business people, interrupting the arms trade and other financial sanctions.
Western allies are calling on Putin to "de-escalate" the crisis, support Ukrainian plans for political reform, return Russian troops in Crimea to their barracks and halt advances into Ukraine and military buildups along its borders.
Monika Scislowska from Warsaw and Geir Moulson from Berlin contributed to this story.
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