KIEV, April 17 – The U.S. Department of State has advised its citizens to defer non-essential travel to Ukraine, as well as cancel all trips to eastern Ukraine and Crimea.

"The Department of State warns U.S. citizens to defer all travel to several regions of Ukraine, including the Crimean Peninsula and eastern regions of Kharkiv, Donetsk, and Luhansk due to the presence of Russian military forces in the Crimean Peninsula and on the eastern border of Ukraine," the Department of State said in a statement posted on the Web site of the U.S. Embassy in Ukraine.

The Department of State said the situation in Ukraine was unpredictable and could change quickly.