The U.S. has warned Russia that the interference with the presidential elections is fraught with "serious consequences," ABCnews reports, citing a senior U.S. official.

According to the source, the “private warning” was made after Director of National Intelligence James Clapper, stated that Kremlin's "senior-most officials" must have authorized cyberattacks on American individuals and political institutions, including the hacks on the servers of the Democratic National Committee.