(Reuters) -U.S. President Donald Trump's administration is preparing for the initial public offerings of mortgage finance giants Fannie Mae and Freddie Mac later this year, the Wall Street Journal reported on Friday.

The plans under discussion could value the companies at roughly $500 billion or more combined, and could fetch $30 billion for the administration, the report said, citing people familiar with the matter.

The companies did not immediately respond to Reuters' requests for comment.

Fannie and Freddie have been under federal conservatorship since 2008 following the financial crisis, during which both entities became insolvent amid the subprime mortgage meltdown.

Exiting conservatorship would mark a key milestone for the companies, which were created by the Congress to support the housing market by ensuring affordable mortgage financing, but crumbled after being severely bruised during the financial crisis.

They were bailed out with taxpayer funds, and the Treasury received preferred shares in return, which paid billions of dollars in dividend over the years.

Over the years, efforts to return them to private control have continued, including under Trump's first term.

Trump also met the CEOs of Citigroup and Bank of America earlier this week to discuss the administration's plans to privatize the mortgage giants, Reuters had reported earlier.

Fannie's shares, which trade over-the-counter, rose 20%. Freddie climbed 15%.

(Reporting by Niket Nishant in Bengaluru; Editing by Anil D'Silva and Shilpi Majumdar)