The US has announced sweeping new sanctions against Russia in retaliation for cyber attacks against the Democratic National Committee and the emails of a key Hillary Clinton adviser that it claims were orchestrated by the Kremlin.

President Barack Obama said that he had signed an executive order to issue sanctions against foreign governments that attempt to interfere in US elections, issuing specific measures against four officials of Russia’s military intelligence unit and two hackers, who it alleged had orchestrated the cyber attacks.

The state department also expelled 35 Russian intelligence operatives stationed in the Russian Embassy in Washington and the Russian Consulate in San Francisco for activity that the US said was “inconsistent with their diplomatic status”. This, it said, was in response to alleged harassment of US diplomats by Russia. The Russian officials have been given 72 hours to leave the country.