President Trump told reporters a few few hours before Rosenstein spoke that he plans to bring up Russia's election interference campaign Monday with President Vladimir Putin when they meet in Helsinki, Finland.
The officers worked for two units of Russian intelligence, one that engaged in active cyber operations by stealing information and another that disseminated the information, Rosenstein announced.
12 Russian intelligence officers have been indicted for hacking the Democratic National Committee, the Democratic Congressional Campaign Committee and the Hillary Clinton campaign, and releasing emails with the intention of impacting the results of the 2016 presidential campaign.
The indictment also does not allege that any vote tallies were altered by hacking.
"The president is fully aware of today's actions by the department", Rosenstein said during a press conference announcing the indictment.
'Free and fair elections are hard-fought and contentious, and there will always be adversaries who work to exacerbate domestic differences and try to confuse, divide, and conquer us'.
Mueller has secured indictments against several former Trump campaign aides, including campaign chairman Paul Manafort, and former White House national security advisor Michael Flynn. And yet, the Mueller team does not believe their efforts influenced the election.
While Friday's indictment does not include any criminal allegations against a US citizen, the charges note that Guccifer 2.0 allegedly communicated with "U.S. persons about the release of stolen documents".
Trump has promised to raise the issue of election meddling with Putin, saying Friday he will "absolutely firmly ask the question" during their meeting.
"We do have a - a political problem where - you know in the United States we have this stupidity going on".
He has been a frequent target of the commander-in-chief, who has consistently attacked Mueller's investigation as "fake news", "a hoax" and "witch hunt" cooked up by Democrats as an excuse for Clinton's election defeat. "But it makes it very hard to do something with Russian Federation".