President Donald Trump could fire Deputy Attorney General Rod Rosenstein "as early as today," as that action is already in play, Weekly Standard Editor Bill Kristol claimed Friday morning.

"I think Rosenstein's firing is very much in play," Kristol said during an MSNBC "Morning Joe" panel discussion.

"It could happen as early as today. I was told earlier this week the president has tasked the White House counsel to sort of give him the memo or give him options explaining how it would work, who would replace Rosenstein under the Vacacines Act, whether it would help him solve his problem."

On Thursday, CNN reported that the White House has been preparing talking points aimed at undermining Rosenstein's credibility. Sources familiar with the plan said Trump's allies plan to portray Rosenstein as having too many conflicts to oversee the Russia investigation, including special counsel Robert Mueller, fairly.

Firing Rosenstein would cripple Mueller's investigation, Democratic Rep. Adam Schiff said Thursday.

"Any replacement of Rod Rosenstein could secretly cripple the Mueller investigation by telling Mueller you can't follow the money and can't investigate this or you need to wrap up that," the nine-term California lawmaker told CNN's Wolf Blitzer.

Kristol said Friday it's important that Republicans defend the rule of law and protect the Mueller investigation "as best as we can," but members of his party have "unfortunately" kept quiet.

Further, he accused the Republican National Committee of attacking former FBI Director James Comey, whose memoir is being released next week, in a "totally unseemly and inappropriate way. They can defend the president if they want, but going after the former FBI director? Just childish, but also very -- I mean it is embarrassing."

"Decent Republicans need to speak up," he added. "They've been quiet so far but silence can be acquiescence and that can be dangerous."

Meanwhile, he warned, firing Rosenstein will make matters even worse for the president, even if it does allow him to buy time.

"We're probably too confident this works out well," he said. "I've been struck listening to the conversation. [Richard] Nixon was forced out of office. Joe Mccarthy ultimately was discredited and mccarthyism went away. We are pretty confident these things work out. That's good. The American system usually works."

Trump, though, "is not stupid in this way and he could get away with it" through a "combination of his pardon power, and his ability to fire people," said Kristol. "The acquiescence of Republicans in Congress, and to some degree around the country, is a very toxic combination."

The key is for Republicans around the country to step up and protect the Mueller investigation, Kristol added, including through lawmakers passing legislation that would prevent Trump from firing him.