Fox News is simply "a wing of the Republican Party," a top White House aide said today.

Appearing on CNN this morning, White House Communications Director Anita Dunn said Fox News exists simply to further the agenda of the GOP.

"Fox News often operates almost as either the research arm or the communications arm of the Republican Party," Dunn said.

This is the second time in a week that Dunn has blasted Fox.

She was quoted in Time Magazine on Thursday blasting the cable network as "opinion journalism masquerading as news."

Fox News Senior Vice President of News Michael Clemente said Fox News' growing viewership speaks for itself. 

"An increasing number of viewers are relying on FOX News for both news and opinion," said Clemente.

He added that Fox has a clear barrier between hard news programming and opinion shows.

"The average news consumer can certainly distinguish between the A section of the newspaper and the editorial page, which is what our programming represents," he said. "So, with all due respect to anyone who still might be confused about the difference between news reporting and vibrant opinion, my suggestion would be to talk about the stories and the facts rather than attack the messenger…which over time, has never worked."

The Obama administration has made a concerted effort to hit back at what it sees as media misinformation.

"The best analogy is probably baseball," White House press secretary Robert Gibbs told Time. "The only way to get somebody to stop crowding the plate is to throw a fastball at them. They move."