WASHINGTON (AP) — President Donald Trump and Secretary of State Marco Rubio are considering firing U.S. Ambassador to Greece Kimberly Guilfoyle after a series of reports alleging she has engaged in improper and possibly illegal conduct before and during her tenure in Athens.

A senior U.S. official said Sunday that Trump and Rubio are “extremely pissed off” by Guilfoyle’s reported conduct and would likely decide on what action to take this week after Monday’s Columbus Day holiday.

The official, who spoke on condition of anonymity to discuss internal deliberations, said Rubio had been particularly angry, not least because he visited Athens just last week and Guilfoyle attended most, if not all, of his events and greeted him on his arrival with a bear hug as the allegations swirled.

In a series of stories, The Wall Street Journal has reported questionable conduct by Guilfoyle, including an alleged threat to a host country official, accepting improper gifts and services and offering to use her influence inside the administration in return for the payment of a large credit card bill.

Guilfoyle has not addressed the reports directly, although her lawyer has said she did nothing wrong and the U.S. Embassy in Athens has tacitly expressed support for her.

After defending Guilfoyle following the first report, Rubio has declined to comment publicly on the growing allegations. On Wednesday, Rubio said: “Our ambassador has been a strong ambassador here.”

But after another report appeared late Wednesday, Rubio on Thursday before leaving Athens berated journalists for asking about the allegations, saying he didn’t know if they were true and that he would not respond if he could not confirm them.

“You guys walk around thinking that because some source told you something and you reported it, it’s the gospel. It’s not the gospel. It’s not the gospel for me. That’s not the way we do things,” Rubio said at the foot of his plane as Guilfoyle, who was there to see him depart, looked on.

The official said that Rubio had grown increasingly frustrated as the reports multiplied.

A second U.S official, who also spoke on condition of anonymity to discuss personnel matters, said the State Department’s inspector general is looking into the allegations, which first began surfacing in the Journal late last month and have since multiplied.

The second official could not say if a formal IG probe had begun. Inspectors general often conduct informal inquiries into complaints against staffers and many times those inquiries do not result in a full-on investigation, which can result in disciplinary action up to and including dismissal.

The State Department has declined to comment on a potential IG investigation.

The top two Democrats on the House Foreign Affairs and Senate Foreign Relations committees, Rep. Gregory Meeks of New York and Sen. Jeanne Shaheen of New Hampshire, as well as the ranking member on the House Committee for Oversight and Government Reform, Robert Garcia, D-Calif., have already called for an investigation into Guilfoyle.

Since late September, the Journal has detailed numerous accounts of questionable conduct by Guilfoyle. Its first report said that she had told guests at a reception that the U.S. could undermine the Greek government if it chose to, promoted the business interests of one particular Greek construction and energy company, and allowed its lobbyist into private diplomatic meetings.

While Rubio was in Athens, the Journal reported — citing text messages — that Guilfoyle had asked a Trump donor and supporter to pay a $100,000 credit card bill just before her confirmation hearing, promising him access to administration officials if he did.

The Journal then reported that Guilfoyle had been enraged about not being invited to a Greek-themed event at the World Economic Forum in Davos, Switzerland, earlier this year and demanded to attend while boasting about luxury travel to France with energy company executives.

Another report, from the British tabloid The Daily Mail, said that Guilfoyle had alienated staff at the U.S. Embassy in Athens and had pushed the bounds of behavior appropriate for the top representative of the U.S. government to Greece.

Guilfoyle is a former Fox News Channel host and California prosecutor who was once engaged to Trump’s son Donald Jr.