House Intelligence Committee ranking member Rep. Adam Schiff said Thursday he has "profound concern" about the way intelligence materials were possibly shared with the panel's chairman.

Two White House officials played a role in giving Republican Rep. Devin Nunes the intelligence reports that fueled his statement that Trump transition team members had information "incidentally" picked up, The New York Times reported Thursday. They are Ezra Cohen-Watnick, senior director for intelligence at the National Security Council, and Michael Ellis, a lawyer who works on national security issues, the Times said, citing "several current American officials."

It heightens questions about Nunes' ability to conduct the House panel's investigation into alleged Russian interference in the 2016 election without White House interference. If the White House had a role in giving Nunes the intelligence, which he then shared with Trump, it could create more doubts about the independence of the probe, which includes looking into any possible links between the Trump campaign and Russia.

At a news conference Thursday, Schiff, a California Democrat, said he has "a lot of unanswered questions" about the process. He raised concerns about why, if the White House did give Nunes the information, it shared the reports with the congressman rather than going directly to the White House.

"Why all the cloak and dagger stuff?" Schiff asked.

The White House repeatedly deflected questions Thursday about whether any Trump administration officials gave Nunes the information. During his daily news briefing, White House press secretary Sean Spicer did not concede if the reporting is correct.

Asked if he would tell reporters if the report was wrong, he said he was "not going to get into it."

The White House invited the chairmen and ranking members of the Senate and House Intelligence Committees to view documents related to the probe, and Schiff said they will do so. Schiff is not sure if those documents are the same ones Nunes saw before making his announcement.

The panels' ranking member insisted that the confusion within the committee will not derail its probe.

"We're not going to get distracted," Schiff said.

A spokesman for Nunes, who served on Trump's transition team, told NBC News that the California congressman will not "confirm or deny speculation about his source's identity."

Nunes has faced increasing pressure, including calls from Democratic colleagues to recuse himself from the Russia probe, after he held a news conference last week to announce that he had seen reports of incidental surveillance of Trump associates. Nunes later admitted to meeting an unidentified source on the White House grounds the day before his news conference.

Critics, including Schiff, have argued that Nunes may no longer be able to conduct an independent investigation. Schiff previously said the Republican chairman did not share the reports about possible Trump transition surveillance with him before announcing what he found.