President Donald Trump tried to fire Robert Mueller, the man overseeing the FBI investigation of possible connections between his campaign and the Russian government, last June.

The New York Times reports tonight the reason the firing didn't happen was because White House Counsel Don McGahn refused to ask the Department of Justice to dump Mueller and instead threatened to quit. Trump then backed down.

Per the Times, here's how Trump planned to claim that Mueller had a conflict of interest justifying his termination:

First, he claimed that a dispute years ago over fees at Trump National Golf Club in Sterling, Va., had prompted Mr. Mueller, the F.B.I. director at the time, to resign his membership. The president also said Mr. Mueller could not be impartial because he had most recently worked for the law firm that previously represented the president's son-in-law, Jared Kushner. Finally, the president said, Mr. Mueller had been interviewed to return as the F.B.I. director the day before he was appointed special counsel in May.

McGahn reportedly told senior staff that firing Mueller would have a "catastrophic" effect on the presidency. He also said that Trump wouldn't fire Mueller on his own if McGahn refused to do it.

The story tonight sheds some new light on reports from late last June that Trump was frustrated with McGahn and lashed out at him for not doing more to stop the Russian probe. And there were reports over the summer that McGahn also nearly quit over frustration that Trump and son-in-law Jared Kushner kept having meetings, and he was concerned it would look like they were coordinating their stories for the investigation.

Read the New York Times report here. The Washington Post just confirmed the story via its own sources. Fox News has also confirmed.

UPDATE: Marshall Cohen of CNN observes that back in August, everybody (including Trump) was denying that firing Mueller was even on the table:

REMEMBER: Trump, his lawyer John Dowd and his top adviser Kellyanne Conway ALL DENIED last August that Trump ever considered firing Mueller. (NYT just reported that Trump ordered Mueller's firing in June.) pic.twitter.com/Li49ecCYSa

— Marshall Cohen (@MarshallCohen) January 26, 2018