House Democratic Leader Nancy Pelosi is calling for Rep. Devin Nunes (R-California) to be removed as chairman of the House Intelligence Committee. This comes as President Trump considers whether to release a classified document by Nunes and other House Republicans alleging misconduct by the FBI in their investigation of the 2016 Trump presidential campaign.

The letter to House Speaker Paul Ryan says Nunes “deliberately and materially” altered the memo after it was voted on by the House, which Pelosi said is a violation of House rules.  

“Even if what they were putting out were true, which it is not, it would be wrong to put that out, because it undermines our security in terms of protecting intelligence sources,” Pelosi told reporters after an event Thursday at the Cambridge Public Library.

The memo focuses on what Republicans say were surveillance abuses by the FBI and the Justice Department in the investigation into potential ties between the Trump campaign and Russia. Democrats have prepared their own memo in response, but Republicans voted to block its release.

Pelosi was asked about President Trump’s decision this week not to impose sanctions against Russia for meddling in the election. Those sanctions had broad bipartisan support in both the House and the Senate.

“It’s really unprecedented,” Pelosi said. “But it begs the question: what do the Russians have on Donald Trump — personally, politically, financially — that he is protecting himself? We need to see the president’s tax returns to see what happened — to whom he is indebted.”