The top Democrat on the House intelligence committee on Friday accused his Republican counterpart of bending to pressure from the White House in his decision to cancel a hearing scheduled for Tuesday in which former top intelligence officials were to testify in connection with a probe encompassing potential ties between President Donald Trump's campaign and Russia.

Rep. Adam Schiff , D-Calif., slammed the committee's chairman, Rep. Devin Nunes, R-Calif., for canceling the hearing over Democrats' objections.

"We strongly object to the cancellation of this hearing," Schiff said in a press conference Friday, shortly after Nunes announced the hearing had been postponed. "We would still urge the majority to reconsider. The witnesses have made it clear that they are still available, and we would urge that that hearing be allowed to go forward."

Nunes said Tuesday's open hearing – which was due to feature the testimony of Director of National Intelligence James Clapper, former CIA Director John Brennan and former acting U.S. Attorney General Sally Yates – had been pushed so the committee could bring back FBI Director James Comey and National Security Agency Director Mike Rogers for a closed session. The pair testified in an open hearing on Monday .

But Schiff said the events of this week – primarily Nunes visiting the White House on Wednesday to discuss intelligence with the Trump administration that the rest of the committee has yet to see – had him suspicious of Nunes' motives.

Nunes has apologized to members of his committee for briefing the public and the White House on what he said was evidence that Trump associates had been swept up in incidental intelligence collection before Democratic members of the committee had the opportunity to review it.

On Friday, Nunes said bringing back Comey and Rogers has "nothing to do with the [new] documents that I've seen."

"I have no objection to bringing [Comey and Rogers back] back and having a closed hearing," Schiff countered. "But I don't think anyone should have any question about what is really going on here. … What really is involved here is the cancellation of the open hearing and I think the rest is designed to simply distract from that point."

"There must have been a very strong pushback from the White House about the nature of Monday's hearing – it's hard for me to come to any other conclusion about why an agreed-upon hearing would be suddenly canceled," Schiff continued. "Clearly it had to do with the events of this week. … So what other explanation can there be? There really is none when these witnesses are ready and available."

Schiff declined to call for Nunes to resign as chairman, saying that decision was one House Speaker Paul Ryan has to make.

"I think the speaker has to decide just as well as our own chairman whether they want a credible investigation being done here, whether they want an investigation that the public can have confidence in," Schiff said. "The events of this week are not encouraging."

But he said Nunes had compromised the integrity of the investigation, and called for an independent commission to conduct a Russia-related probe.