WASHINGTON (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.