Washington (CNN) Former FBI Director James Comey took to Twitter to weigh in as rumors swirl around the FBI's reported opposition to a secret memo's potential declassification.

"All should appreciate the FBI speaking up," Comey wrote Thursday evening. "I wish more of our leaders would. But take heart: American history shows that, in the long run, weasels and liars never hold the field, so long as good people stand up. Not a lot of schools or streets named for Joe McCarthy."

All should appreciate the FBI speaking up. I wish more of our leaders would. But take heart: American history shows that, in the long run, weasels and liars never hold the field, so long as good people stand up. Not a lot of schools or streets named for Joe McCarthy. — James Comey (@Comey) February 1, 2018

Although Comey does not directly address the memo, it suggests a reference to the FBI reportedly taking issue with the idea of publicly releasing a memo produced by House Intelligence Chairman Devin Nunes, a California Republican.

The news of the memo came as the House Intelligence Committee is investigating Russian meddling in the 2016 US election. It's one of several inquiries into potential ties between the Trump campaign and Russia.

CNN previously reported that FBI Director Christopher Wray was at odds with President Donald Trump over the memo, which is under review by the White House.

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