Prime Minister Dmitry Medvedev issued a veiled warning about China's rising influence in Russia's resource-rich Far East, saying it was essential to defend the area against "excessive expansion by bordering states".
Speaking days after Russia's first deputy defence minister said two new nuclear submarines would be sent to the Pacific Fleet, Medvedev also said it was "important not to allow negative manifestations ... including the formation of enclaves made up of foreign citizens."
His comments, some of the strongest on the subject yet, underlined the Kremlin's suspicions that a steady influx of Chinese migrants may ultimately pose a threat to Russian hegemony in the remote and sparsely populated territories of Siberia and the Far East.
Russia and China enjoy strong diplomatic and trade relations and have joined forces in the United Nations Security Council to block proposed sanctions on President Bashar al-Assad of Syria. But growing Chinese influence in Russia's Far East - where street signs are often in both Russian and Chinese - has long been a source of tension.
Resource-rich Russia is the world's largest country by territory, but has seen its population of 143 million people fall in recent years, while resource-hungry China, situated immediately to the south, has a rising population of over 1.3 billion people.
Medvedev, who was president from 2008 until May, raised the sensitive subject at a government meeting during a broader discussion of migration.
"Not many people live there, unfortunately, and the task of protecting our Far Eastern territories from excessive expansion by bordering states remains in place," he said.
New Migration Policies
Russia has tried to counter-balance China's growing influence in its Far East by boosting its own political and military presence in the region, where it has seen its own influence weaken.
Medvedev's new government, formed in May, included for the first time a Ministry of the Far East to underpin other state programmes already in place. One such programme has brought 400 families from other former Soviet republics to the area to reinforce its Russian-speaking population.
Medvedev said new migration policies had been drawn up by President Vladimir Putin and told ministers to draft an action plan aimed at turning the policies into reality.
Putin wrote earlier this year that minorities must live under the umbrella of Russian culture, and that migrants must pass exams in Russian language and history.
He also said that the authorities should be given more power to vet migrants' professional skills and that students should read some 100 national classics.
Moscow and Beijing have signed a slew of economic and energy agreements in recent years and will probably use an Asia Pacific Summit, which Russia will host in the Far Eastern city of Vladivostok in September, to ink more deals.