WASHINGTON —President Trump said Sunday that he is not considering firing special counsel Robert Mueller even as his administration was again forced to grapple with the growing Russia probe that has shadowed the White House for much of his initial year in office.

Trump returned to the White House from Camp David and was asked if he would consider triggering the process to dismiss Mueller, who is investigating whether the president’s Republican campaign coordinated with Russian officials during last year’s election.

The president answered: “No, I’m not.”

But he did add to the growing conservative criticism of Mueller’s move to gain access to thousands of emails sent and received by Trump officials before the start of his administration, yielding attacks from transition lawyers and renewing chatter that Trump may act to end the investigation.

“It’s quite sad to see that, my people were very upset about it,” Trump said. “I can’t imagine there’s anything on them, frankly. Because, as we said, there’s no collusion. There’s no collusion whatsoever.”

Many Trump allies used the email issue as another cudgel with which to bash the probe’s credibility.

Members of the conservative media and some congressional Republicans have begun to systematically question Mueller’s motives and credibility while the president himself called it a “disgrace” that some texts and emails from two FBI agents contained anti-Trump rhetoric.

One of those agents was on Mueller’s team and has been removed.

Michael Caputo, a former Trump campaign aide, called the investigation an “attack on the presidency” and told CNN there are “more and more indications that the Mueller investigation is off the rails.”

The talk of firing Mueller has set off alarm bells among many Democrats, who warn it could trigger a constitutional crisis.

Some Republicans also advised against the move, including Sen. John Cornyn of Texas, who deemed the idea “a mistake.”

The rumor mill overshadowed the Republican tax plan, which is due to be voted on this week. Although Treasury Secretary Steve Mnuchin was doing a victory lap on the tax bill on the Sunday talk show circuit, he first had to field questions on CNN’s “State of the Union” about whether he believed Trump would trigger the process to fire Mueller.

“I don’t have any reason to think that the president is going to do that, but that’s obviously up to him,” Mnuchin said.

Mnuchin added that “we have got to get past this investigation, it’s a giant distraction” but declined to elaborate on how he would want it to end.

Marc Short, the White House director of legislative affairs, was also peppered with questions about Mueller’s fate during his own appearance on NBC’s “Meet the Press” and again urged a quick end to the investigation but insisted that Trump has not discussed firing Mueller.

“There’s no conversation about that whatsoever in the White House,” Short said.

The tax bill measure would give the largest breaks to the richest Americans, but Trump has tried to sell the bill as a “Christmas present” for middle-class Americans in part because it would trigger job growth.

“As a candidate, I promised we would pass a massive TAX CUT for the everyday working American families who are the backbone and the heartbeat of our country. Now, we are just days away…” Trump said in a tweet from Camp David, where he spent the weekend.