WASHINGTON -- Friday's release of a once-classified CIA memo is "unprecedented" and could have far-reaching effects in foreign policy, former CIA director Leon Panetta told CBS News' justice and homeland security correspondent Jeff Pegues. The memo claims that FBI agents relied primarily on a politically-motivated dossier compiled by former British spy Christopher Steele when they sought permission to surveil Trump campaign foreign policy adviser Carter Page just before the 2016 election.

"All of this sends a terrible message to our allies who are going to worry about sharing classified information that is so easily released as part of this political effort," Panetta said.

President Trump gave his approval for Republicans to release the memo written by House Intelligence Committee member Devin Nunes, alleging a "troubling breakdown of legal processes" at the start of the Russia investigation.

The memo says that when agents went before a secret FISA court judge, they did "not mention Steele was ultimately working on behalf of -- and paid by -- the DNC and Clinton campaign" to the tune of about $160,000, CBS News' Nancy Cordes reports.

"A lot of people should be ashamed of themselves -- and much worse than that," Mr. Trump said Friday.

House Republicans have described the memo as a breach of civil liberties.

"To my knowledge this is the first time in American history that the FBI and Justice Department have been weaponized the actions of a political party," said U.S. Rep. Matt Gaetz, R-Florida.

The FBI had opposed the memo's release, citing "grave concerns about material omissions of fact."

The top Democrat on the Intelligence Committee told reporters by phone the FBI had revealed Steele's political ties.

"This isn't about oversight," said Adam Schiff, D-California. "This is about telling a political story that's helpful to the president, about telling a political story that is designed to injure the work of the special counsel and to discredit it."

Nunes said on Fox News Friday that he has "an obligation to the American people, when we see FISA abuse. The American citizens that are represented before this have to be protected."

But FBI agents knew Russians were courting Page three years before the dossier was written.

Fired FBI director James Comey tweeted Friday: "That's it? Dishonest and misleading memo wrecked the House Intel Committee, destroyed trust with intelligence community...for what?"