Director of National Intelligence John Ratcliffe on Wednesday said he had approved the release of almost 1,000 pages of materials to the Justice Department as part of an investigation of the FBI’s probe of Russian election interference in 2016.

The decision follow’s Ratcliffe’s earlier declassification of handwritten notes by former CIA director John Brennan, which current and former officials have criticized as a political maneuver to bolster President Trump’s claims that Brennan and other former Obama administration officials conspired to fabricate connections between his campaign and Russia.

The FBI’s probe of Russian election interference examined potential links between Russia and the Trump campaign, as did Special Counsel Robert S. Mueller III, who did not establish sufficient evidence to substantiate a criminal conspiracy.

The investigation has long angered Trump, who derides it as a “hoax” meant to undermine his campaign and his presidency. Trump has posted about the investigation to his Twitter account dozens of times in the past 24 hours, tweeting on Tuesday that he had “fully authorized the total Declassification of any & all documents” on the investigation.

The information Ratcliffe provided to the Justice Department on Wednesday consisted of hundreds of pages of classified material and was a second batch provided to U.S. Attorney John Durham, who is investigating the origins of the FBI’s Russia probe, according to a senior administration official.

The official said Ratcliffe had not declassified the material and acknowledged that Trump’s recent comments had renewed intelligence officials’ focus on the president’s desire to provide more information to Durham’s investigation.

On Tuesday, Ratcliffe declassified a heavily redacted set of notes written by Brennan that appear to show he briefed President Barack Obama in 2016 on intelligence the U.S. had obtained from Russian sources, indicating that Hillary Clinton had approved a plan to try to tie the hacking of Democratic emails by Russia to the Trump campaign.

Ratcliffe said in his letter that the intelligence was not verified and that it was not clear whether it reflected “exaggeration or fabrication” by Russia. A former U.S. official said analysts were aware that Russian officials discussed matters knowing their conversations might be intercepted or discovered and deliberately planted false or misleading statements.

Senior intelligence officials objected to releasing the Brennan notes, fearing that it could give credence to unsubstantiated disinformation from the Kremlin, according to people familiar with the matter, who, like others, spoke on the condition of anonymity to discuss sensitive information.

Ratcliffe’s disclosures, as well as his provision of new documents to Durham, follows mounting pressure from Republican lawmakers to disclose more classified material about the Russia probe.

Also on Wednesday, GOP Sens. Charles E. Grassley (Iowa) and Ron Johnson (Wis.) wrote to CIA Director Gina Haspel demanding that she provide information they said is in the agency’s possession that pertains to the FBI’s investigation.

A CIA spokesperson did not respond to a request for comment.