MOSCOW

The US Embassy in Russia urged its citizens on Wednesday to refrain from traveling to Russia, and those, who are already in the country, to leave immediately. 

In a security alert published on its website, the US mission said Moscow may call people having dual Russian-US citizenship for military service.

Russian President Vladimir Putin announced a partial military mobilization, calling up to 300,000 reservists for deployment to Ukraine, where Moscow began a "special military operation" in February.

The embassy said flight options are extremely limited at present, but overland routes by car and bus are still open.

"If you wish to depart Russia, you should make independent arrangements as soon as possible. The U.S. Embassy has severe limitations on its ability to assist U.S. citizens, and conditions, including transportation options, may suddenly become even more limited. U.S. citizens should not travel to Russia and those residing or travelling in Russia should depart Russia immediately while limited commercial travel options remain," the embassy said.