President Donald Trump has spoken with advisers about firing Attorney General Jeff Sessions, officials say, and launched a fresh Twitter tirade Tuesday against the man who was the first U.S. senator to endorse his candidacy.

“Attorney General Jeff Sessions has taken a VERY weak position on Hillary Clinton crimes (where are E-mails & DNC server) & Intel leakers!” Trump tweeted.

The president’s anger over Sessions’ decision to recuse himself from the government’s investigation of Russian meddling in the U.S. election had burst into public view Monday when he referred to Sessions in a tweet as “beleaguered.” Privately, Trump has speculated aloud to allies in recent days about the potential consequences of firing Sessions, according to three people who have recently spoken to the president. They spoke on condition of anonymity to discuss private conversations.

On Tuesday, White House press secretary Sarah Huckabee Sanders told Fox News’ “Fox & Friends” that the president is “frustrated and disappointed” with Sessions for recusing himself from the Russia probe.

“That frustration certainly hasn’t gone away. And I don’t think it will,” she said.

Trump often talks about making staff changes without following through, so those who have spoken with the president cautioned that a change may not be imminent or happen at all.

“So why aren’t the Committees and investigators, and of course our beleaguered A.G., looking into Crooked Hillarys crimes & Russia relations?” the president tweeted Monday. His tweet came just hours before his son-in-law, White House senior adviser Jared Kushner, traveled to Capitol Hill to be interviewed about his meetings with Russians.

Trump’s rapid-fire tweeting resumed at daybreak Tuesday, with the president wondering aloud about Sessions’ “VERY weak” position on “Hillary Clinton crimes.”

In another post to his Twitter account, Trump said: “Ukrainian efforts to sabotage Trump campaign — quietly working to boost Clinton. So where is the investigation A.G.”

He also mocked the Russia investigation in congress, suggesting that Congress might want to talk to his 11-year-old son after it finished with Kushner.

“Jared Kushner did very well yesterday in proving he did not collude with the Russians. Witch Hunt. Next up, 11 year old Barron Trump!” he tweeted.

Trump’s intensifying criticism of Sessions has fueled speculation that Sessions may resign even if Trump opts not to fire him. During an event at the White House, Trump ignored a shouted question about whether Sessions should step down. The attorney general said last week he intended to stay in his post.

If Trump were to fire Sessions, Deputy Attorney General Rod Rosenstein would be elevated to the top post on an acting basis. That would leave the president with another attorney general of whom he has been sharply critical in both public and private for his handling of the Russia probe, according to four White House and outside advisers who, like others interviewed, spoke on condition of anonymity to discuss private conversations.

It could also raise the specter of Trump asking Rosenstein — or whomever he appoints to fill the position — to fire Robert Mueller, the special counsel leading the investigation into Russia’s meddling in the 2016 election and potential collusion with Trump’s campaign.

The name of one longtime Trump ally, Rudy Giuliani, was floated Monday as a possible replacement for Sessions, but a person who recently spoke to the former New York City mayor said that Giuliani had not been approached about the position. Giuliani told CNN on Monday that he did not want the post and would have recused himself had he been in Sessions’ position.

The president’s tweet about the former Alabama senator comes less than a week after Trump, in a New York Times interview, said that Sessions should never have taken the job as attorney general if he was going to recuse himself. Sessions made that decision after it was revealed that he had met with a top Russian diplomat last year.

Trump has seethed about Sessions’ decision for months, viewing it as disloyal — arguably the most grievous offense in the president’s mind — and resenting that the attorney general did not give the White House a proper heads-up before making the announcement that he would recuse himself. His fury has been fanned by several close confidants — including his son Donald Trump Jr, who is also ensnared in the Russia probe — who are angry that Sessions made his decision.

Trump and Sessions’ conversations in recent weeks have been infrequent. Sessions had recently asked senior White House staff how he might patch up relations with the president but that effort did not go anywhere, according to a person briefed on the conversations. Sessions was in the West Wing on Monday but did not meet with the president, according to deputy press secretary Sarah Huckabee Sanders.

Newt Gingrich, a frequent Trump adviser, said that the president, with his criticisms of Sessions, was simply venting and being “honest about his feelings. But that doesn’t mean he’s going to do anything,” Gingrich said. Still, he said the president’s comments would have repercussions when it comes to staff morale.

“Anybody who is good at team building would suggest to the president that attacking members of your team rattles the whole team,” Gingrich said.

Sessions and Trump used to be close, sharing both a friendship and an ideology. Sessions risked his reputation when he became the first U.S. senator to endorse the celebrity businessman and his early backing gave Trump legitimacy, especially among the hard-line anti-immigration forces that bolstered his candidacy.

After Trump’s public rebuke last week, Sessions said, “I’m totally confident that we can continue to run this office in an effective way.”

Attorney General Jeff Sessions has taken a VERY weak position on Hillary Clinton crimes (where are E-mails & DNC server) & Intel leakers!

— Donald J. Trump (@realDonaldTrump) July 25, 2017

Problem is that the acting head of the FBI & the person in charge of the Hillary investigation, Andrew McCabe, got $700,000 from H for wife!

— Donald J. Trump (@realDonaldTrump) July 25, 2017

(AP)