Former White House Chief Strategist Stephen K. Bannon believes Senate Majority Leader Mitch McConnell (R-KY) and House Speaker Paul Ryan (R-WI) are trying to “nullify” the 2016 election because they do not believe in the economic nationalist agenda that got President Donald Trump elected.

In an interview with CBS anchor Charlie Rose that will air on Sunday’s 60 Minutes, Bannon said that is why he is going to “war” with the Republican establishment. He also revealed that McConnell even told Trump’s team to “back off” the “drain the swamp” talk during one of their first meetings.

“The Republican establishment is trying to nullify the 2016 election,” Bannon told Rose, in a clip that the CBS Evening News previewed on Thursday evening. “That’s a brutal fact we have to face.”

When Rose asked him to name names, Bannon answered, “I think Mitch McConnell, and to a degree, Paul Ryan. They do not want Donald Trump’s populist, economic nationalist agenda to be implemented. It’s very obvious.”

Bannon then told Rose that during one of the first meetings with McConnell at Trump Tower, the Senate Majority Leader told Trump’s team, “I don’t wanna hear any more of this ‘drain the swamp’ talk.”

The Breitbart News executive chairman said McConnell told them that “a guy up on Capitol Hill can’t buy a Coke unless it’s gotta be reported” and, as a result, he “can’t hire any smart people.”

McConnell, according to Bannon, insisted Trump’s team stop talking about draining the swamp, saying, “you gotta back off that.”

Bannon also told Rose that Messrs. Ryan and McConnell are not going to help Trump “unless they’re put on notice. They’re gonna be held accountable if they do not support the President of the United States. Right now there’s no accountability. They do not support the president’s program. It’s an open secret on Capitol Hill. Everybody in this city knows it.”

Rose then asked, “now that you’re out of the White House, you’re going to war with them?”

Bannon replied, “absolutely.”