Russia's point man for arms control cautioned Donald Trump's incoming administration on Friday against resuming nuclear testing, saying Moscow would keep its own options open amid what he said was Washington's "extremely hostile" stance.

Deputy Foreign Minister of the Russian Federation Sergei Ryabkov said American policy is "extremely hostile" toward Russia.

Russia warns of potential nuclear testing in response to Trump's stance, raising concerns about global security.

The Russian government has been a historic opponent of bitcoin, banning its use for domestic payments, but has recently come to see the potential benefits of virtual currencies for evading U.S. and Western sanctions.

Russian companies are using bitcoin to evade Western sanctions, thanks to a new law, the country's Finance Minister Anton Siluanov confirmed in a television interview. Why it matters: Russia's economy has been hampered by difficulties in making and receiving international payments,