(Reuters) - U.S. President Donald Trump has not contacted the Federal Communications Commission about its lack of approval for Sinclair Broadcast Group's SBGI.O deal to buy Tribune Media Co TRCO.N, which Trump has called "disgraceful" on Twitter, FCC Chairman Ajit Pai said on Thursday.

FILE PHOTO: Chairman Ajit Pai speaks ahead of the vote on the repeal of so called net neutrality rules at the Federal Communications Commission in Washington, U.S., December 14, 2017. REUTERS/Aaron P. Bernstein/File Photo

“No one in the White House has contacted us to express a view about the merger,” Pai said.

In July, the FCC unanimously voted to refer the merger for an administrative review to determine if the conservative-leaning Sinclair engaged in misrepresentation or displayed a lack of candor about the merger to the commission.

Trump’s tweet raised the question of whether he had involved himself in the decision-making progress of an independent regulator.

In its order for administrative review, the FCC said Sinclair “did not fully disclose facts” about the $3.9 billion acquisition. Pai had expressed “serious concerns” prior to the vote.

Within days of the FCC action, Trump tweeted: “So sad and unfair that the FCC wouldn’t approve the Sinclair Broadcast merger with Tribune. This would have been a great and much needed Conservative voice for and of the People.”

The Republican president said it was "disgraceful" that the FCC was standing in the way of the merger, which he compared to a 2011 FCC approved deal in which Comcast Corp CMCSA.O acquired NBC.

On Thursday, Pai reiterated previous statements to Congress defending the decision to review.

“I will simply say what I said to Congress, which is, I stand by our decision. We looked at the facts and applied the law as we do in any transaction.”

Sinclair owns 192 stations, the largest number of local TV stations in the United States. The company said in May 2017 it planned to acquire 42 new stations from the Tribune. But it had said it would sell 23 of its existing stations to obtain regulatory approval.

The administrative review hearing could cause significant delays and potentially kill the deal.