(Reuters) - U.S. President Barack Obama said he learned through news reports that Hillary Clinton used a personal email account for official business while she served as his secretary of state, CBS News reported on Saturday.

"I'm glad that Hillary’s instructed that those emails about official business need to be disclosed," Obama said, according to an excerpt of an interview with CBS released by the network.

Clinton, seen as the front-runner for the Democratic Party's presidential nomination in 2016, said on Wednesday she wanted the State Department to release the emails quickly.

"I think that the fact that she is putting them forward will allow us to make sure that people have the information they need," Obama said in the interview, versions of which will be aired on Sunday morning on CBS.

"The policy of my administration is to encourage transparency, which is why my emails, the Blackberry I carry around, all those records are available and archived," Obama added.

The growing controversy over Clinton's use of personal email for work while she was U.S. secretary of state threatens to cloud the expected launch of her campaign.

Clinton tried to quell the growing controversy late on Wednesday, saying she wanted the State Department to release the emails quickly. But a senior State Department official told Reuters on Thursday the task would take time.

"The review is likely to take several months given the sheer volume of the document set," the official said.

The State Department has said there was no prohibition during Clinton's tenure on using personal email for official business as long as it was preserved.

A total of 55,000 pages of documents covering the time Clinton was in office has been turned over, according to the State Department. But Clinton and her aides controlled that process, and the emails were not archived on government servers.

(Reporting by Mohammad Zargham; Editing by James Dalgleish)