(CNN) President Donald Trump shared highly classified information with Russian foreign minister Sergey Lavrov and Russian ambassador Sergey Kislyak during a meeting in the Oval Office last week, according to reporting by the Washington Post.

This latest blunder comes within a calendar week that's seen the stunning dismissal of FBI Director James Comey, a series of inaccurate explanations for why it was done and Trump threatening the former director while floating the possibility that he is taping phone conversations in the White House.

That series of self-inflicted wounds has congressional Republicans mystified and scared, desperately trying to figure out what Trump will do next and, as importantly, what it all means for their own political prospects. To date, Republicans have stood by Trump or at least stayed silent in the face of his many foibles. But, in a number of conversations Monday evening with Republican House members and GOP strategists, there was a widespread feeling that this time Trump might have gone too far.

"On strategy and tactics, most Republican members of Congress will likely give the President a wide berth, but on mistakes or issues that don't appear to be based on some bigger strategy, I think those same members of Congress will begin to speak out," said one senior Republican House member granted anonymity to speak candidly. "The sharing of classified information to the Russians clearly falls into the second bucket. There is a honeymoon period, but on issues like this, if the honeymoon isn't over yet, it will be soon."

That sentiment was echoed by a prominent GOP consultant I spoke to who asked not to be named to offer a candid assessment of Trump and congressional Republicans.

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