Updated

European Union leaders are holding an emergency summit to decide on imposing sanctions against Russia over its military incursion in Ukraine's Crimean peninsula.

The EU leaders were gathering Thursday as the 28-nation bloc seeks to find the right response to the conflict unfolding just beyond its eastern border in Ukraine.

British Prime Minister David Cameron said that Europe "needs to send a very clear message to the Russian government that what has happened is unacceptable and should have consequences."

Lithuanian President Dalia Grybauskaite said"Russia today is dangerous."

The EU on Monday told Russia to withdraw its troops on the Crimean peninsula to its barracks or face sanctions. Among the initial punitive measures considered are suspending talks with Russia on visa liberalization and an economic agreement.