Determining the facts of Russian meddling in the presidential campaign will take a trustworthy, “bipartisan” investigation — and House Intelligence Committee Chairman Devin Nunes (R-Calif.) wiped out the opportunity for that in the House, Sen. John McCain (R-Ariz.) declared Sunday.

“If we’re really going to get to the bottom of these things, it’s got to be done in a bipartisan fashion. And as far as I could tell, Congressman Nunes killed that,” McCain said on ABC’s “This Week.”

McCain was responding to a question about Nunes’ trip to the White House grounds earlier this month when he was given access to secret intelligence by White House officials, which Nunes promptly shared with Donald Trump — but not with his own committee. McCain called the entire procedure “bizarre.”

McCain said it’s important for both Democrats and Republicans to work “closely together,” especially on the armed forces and intelligence panels. “We have to,” said McCain, who chairs the Senate Armed Services Committee. “It’s for the good of the security of the nation and the men and women who serve us.”

He praised the Senate Intelligence Committee, which is holding hearings on the Russia investigation while the House probe is stalled.

Nunes said the documents indicated that Trump and others may have been incidentally surveilled while intelligence officials conducted an investigation on others. It was mentioned as possible support for Trump’s claims — denied by the FBI — that President Barack Obama ordered surveillance of the businessman during the presidential campaign. Nunes later conceded that he couldn’t be certain Trump was monitored.

Adam Schiff (Calif.), the ranking Democrat on the House Intelligence Committee, who has now seen the same information, said he saw no reason intelligence documents were not shared with the congressional intelligence committees.

McCain also spoke briefly about Syria and Secretary of State Rex Tillerson’s recent comment that the “Syrian people” will determine the “longer-term status of President Assad.”

“That is one of the more unusual statements I’ve ever heard,” the senator said. “I know that Mr. Tillerson was busy, but did he miss the barrel bombing? Did he miss the Iranian Revolutionary Guard? Did he miss the Russians striking with precision weapons in Aleppo, deliberately killing people in hospitals?”

He added: “And to say now we’re going to turn our backs on these people? What about the thousands that we trained and equipped? What about those people? What signal do we send people who struggle for freedom around the world? That Syria is determining its own future?”