Russian troops and military planes were flowing into Crimea yesterday in violation of accords between the two countries, Ukrainian border guards said.
Over the last 24 hours, 10 Russian combat helicopters and eight military cargo planes have landed on the flashpoint Black Sea peninsula, the guards said in a statement, while four Russian warships have been in the port of Sevastopol since Saturday.
Kiev received no warning regarding the troop movements, even though that is required by the international laws regarding the stationing of Russia's Black Sea navy in Crimea.
Under these agreements, Ukraine should receive notice of any troop movements 72 hours in advance.
Meanwhile Moscow yesterday formally launched a project to build a bridge to Ukraine's Crimea, as armed men believed to be Russian took the Black Sea peninsula under almost complete control.
The decree signed by Prime Minister Dmitry Medvedev names Russia's state company Avtodor as the main contractor for the project and for engineering studies to be completed by November 2014.
"We are watching the way the situation develops, but there are decisions that have binding character," Medvedev said of the bridge, which was agreed between Russia and the former Ukrainian government of now ousted president Viktor Yanukovych.
President Vladimir Putin at the weekend received a green light from parliament to use armed forces in Ukraine due to a "threat to the lives of Russian citizens" on its Crimean peninsula.
The Black Sea peninsula is under de-facto occupation by Russian military which has been embraced by the local Russian speaking population fearing Kiev's new authorities.