WASHINGTON, June 13 (Reuters) -

Nippon Steel's ( NISTF ) $14.9 billion bid for U.S. Steel

poses a national security risk, but those concerns can be

mitigated if the companies fulfill certain conditions laid out

by the Trump administration, U.S. President Donald Trump said in

a executive order on Friday.

"I additionally find that the threatened impairment to the

national security of the United States arising as a result of

the Proposed Transaction can be adequately mitigated if the

conditions set forth in section 3 of this order are met," Trump

said in the order released by the White House.