Washington (CNN) A top Democratic congressman said Friday he is "very concerned" about the possibility that President Donald Trump will fire Deputy Attorney General Rod Rosenstein in the wake of a controversial memo alleging FBI abuses of its surveillance authority.

"I'm very concerned about it," Rep. Adam Schiff, D-California, said Friday on CNN's "The Situation Room." "There's no telling what this President is capable of."

Schiff is the top Democrat on the House Intelligence Committee, and his comments came hours after Trump approved the public release of a memo spearheaded by the committee's chairman, Rep. Devin Nunes, R-California.

The Republican-crafted memo alleges the FBI abused its power during the 2016 election, and says Rosenstein approved at least one FISA application for former Trump campaign adviser Carter Page. Rosenstein currently oversees the special counsel investigation into possible Trump-Russia ties during the 2016 election. When asked if he was considering firing Rosenstein , Trump refused to say either way.

"You figure that one out," Trump said Friday.

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