A US federal judge on Wednesday grilled a senior member of Donald Trump's Justice Department during a hearing over the department's controversial decision to drop corruption charges against New York Mayor Eric Adams.

The move has sparked resignations within the Justice Department and the mayor's office, amid allegations of a quid pro quo in exchange for Adams supporting the Republican president's immigration policies — a claim Adams denies.

Judge Dale Ho made no decision on the effort to abandon the graft case against Adams during the 90-minute hearing, asking for "patience" as he weighs what he called a "somewhat unusual situation."

"It's not in anyone's interest for this to drag on," Ho said, but "I'm not going to shoot from the hip right here on the bench."

He acknowledged the scope of his power to contradict the Justice Department on the matter was "narrow."

Acting Deputy Attorney General Emil Bove appeared alone before the judge to defend his office's demand, which he said was necessary so Adams can focus on "protecting the city."

Bove's likely superior, Todd Blanche, who is awaiting Senate confirmation to become the deputy attorney general, sat in the front row of the courtroom packed with media and legal experts.

Both Bove and Blanche were on the team that defended Trump as he was criminally convicted for business fraud in a New York state court last year.

Bove said the ongoing case against Adams "interferes with the president's efforts in the national security realm."

He and Alex Spiro, the mayor's lawyer, said the indictment stripped Adams of his security clearance and he was thus unable to participate in a federal task force on immigration "in a full, candid, complete way."

Bove said the case was impeding the mayor's ability to govern and campaign to keep his position.

That argument contradicts what Adams — who is up for reelection in November, with a competitive Democratic primary in June — has been insisting for months: that the fraud and bribery charges are not distracting from his mayoral duties to the largest US city.

Ho asked Adams under oath a series of questions, notably to ensure the mayor understood the charges would not necessarily be put to bed forever — the federal government, including the Trump administration, could revive them.

"Yes I understand," Adams said. "And judge, I have not committed a crime, and I don't see them bringing it back."

Calls for Adams to resign

If his presence in the courtroom was a show of measured intimidation, Bove held nothing back in a statement later.

"I went to New York today to show the men and women of the Justice Department as well as the American people that I am personally committed to our shared fight: ending weaponized government, stopping the invasion of criminal illegal aliens, and eliminating drug cartels and transnational gangs from our homeland," he said.

"For those who do not support our critical mission, I understand there are templates for resignation letters available on the websites of the New York Times and CNN."

There was no counterweight present at the hearing to the viewpoints of Bove and Adams's legal team: the acting US attorney in Manhattan, Danielle Sassoon, along with the lead prosecutor on the case both dramatically resigned last week.

The latter, Hagan Scotten, told Bove in his blistering letter that only a "fool" or a "coward" would comply with the department's demand to drop the charges against Adams.

Adams left Wednesday's hearing with a smile and thumbs up.

But the embattled mayor is facing growing pressure from high-ranking figures to resign, as the suggestion that he is beholden to the Trump administration triggers widespread condemnation, including from voters.

Governor Kathy Hochul, who has the power to remove Adams from office, met with "key leaders" Tuesday to discuss what she called a "path forward with the goal of ensuring stability for the City of New York."

Bove's stunning incursion into an ongoing anti-corruption case of a public official has rattled the legal community, as sweeping shakeups at the Justice Department have seen top officials fired, demoted or reassigned.

More than 800 former federal prosecutors released an open letter Monday condemning recent actions by Trump's Justice Department that are not based on "the facts and the law" but appear intended "to serve solely political purposes."