MOSCOW (AFP) - Russia said on Thursday it was stepping up field training for tank, artillery and infantry units in three regions next to the Ukrainian border in a powerful display of military might.
The move came as thousands of paratroopers also began exercises close to Ukraine on Thursday, while Russian gunmen patrol Crimea ahead of a referendum on it joining Russia on Sunday.
The armed forces are "increasing the intensity of field training exercises", the defence ministry said in a statement, saying the exercises were being carried out in the Rostov, Belgorod and Kursk regions bordering Ukraine, as well as one non-border region.
"The main aim... is a multi-faceted check of the units' cohesiveness followed by the performance of battle training assignments in unfamiliar terrain and untested firing ranges," the ministry said.
It said the exercises would continue until the end of March but did not specify how many troops were involved.
In a separate drill, 4,000 paratroopers launched exercises in the Rostov region on Thursday set to continue until March 14, the ITAR-TASS news agency cited the defence ministry as saying. Russian state television showed hundreds of parachutes floating down to land.
Deputy Defence Minister Anatoly Antonov said on Wednesday that Moscow had permitted a request for a Ukrainian reconnaissance plane to carry out an observation flight over the border regions.
A senior Russian lawmaker late on Wednesday apparently let slip that the uniformed gunmen deployed Crimea ahead of its Sunday referendum on joining Moscow were Russian troops.
"Now there are some military units there who are occupying positions in case there is such resistance, armed aggression, armed expansion from Kiev," the head of the State Duma's committee for relations with ex-Soviet states, Leonid Slutsky, told Echo of Moscow radio station.
President Vladimir Putin had previously insisted the gunmen were local volunteer groups.
Russia earlier held a massive snap check of battle readiness involving thousands of troops in central and Western Russia on Putin's orders from Feb 26 to March 4.