Ukraine has restored military conscription to deal with increasingly violent pro-Russian separatists who have seized buildings in about a dozen cities in Ukraine's Russian-speaking east.
Interim President Oleksandr Turchynov signed the conscription decree Thursday, just hours after Russian President Vladimir Putin demanded that Ukraine withdraw all military personnel from the troubled region near the Russian border.
Mr. Putin made the demand in a phone conversation with German Chancellor Angela Merkel, who meets with U.S. President Barack Obama Friday in Washington. Russia's Interfax news agency said Mr. Putin also stressed the need for "a broad national dialogue" in Ukraine involving all regions and political forces.
The Ukrainian conscription decree, which targets 18-25-year-olds, was signed a day after the Ukrainian leader said his government was "helpless" to quell the growing pro-Russian separatist movement in two eastern regions.
Mr. Turchynov also conceded Wednesday that his government had lost control of its own troops in southeastern Ukraine.
Meanwhile, club-wielding pro-Russian demonstrators on Thursday marked May Day by storming the prosecutor's office in the eastern Ukrainian industrial hub of Donetsk. Protesters already control a number of key buildings in the city, and have declared a May 11 referendum on whether to secede from Ukraine and join Russia.
A similar vote last month led to Russia's annexation of the Crimean peninsula.
In Ukraine's capital, Kyiv, Thursday, hundreds of people joined a rally for peace and unity that was organized by student and trade union groups. Marchers called for constitutional reforms, new parliamentary elections and a national referendum on whether Ukraine should become a federal state.
In Moscow, tens of thousands of people marched through Red Square, some of them carrying flags of the former Soviet Union. Russian television also showed footage of a May Day parade in the capital of the Crimean peninsula -- a largely Russian-speaking Ukrainian territory annexed by Moscow in March despite widespread opposition in the West. One banner in the Simferopol march read: "Crimea is Russia. Welcome home."