(CNN) — The Manhattan grand jury investigating former President Donald Trump is not concluding this week, with questions swirling over how close the grand jury is to bringing an indictment — or if it actually will at all.

While there’s been radio silence from Manhattan District Attorney Alvin Bragg over the past several days about the status of the investigation amid widespread media and political speculation, the district attorney’s office reiterated that the public will know when the investigation has reached its conclusion.

“The District Attorney pledged that the DA’s Office would ‘publicly state the conclusion of our investigation whether we conclude our work without bringing charges, or move forward with an indictment.’ He stands by that pledge,” Bragg’s general counsel, Leslie Dubeck, wrote in a letter to congressional Republicans on Thursday criticizing their plans to investigate the Trump probe.

“And if charges are brought at the conclusion, it will be because the rule of law and faithful execution of the District Attorney’s duty require it,” Dubeck added.

The Manhattan grand jury did not hear the Trump case when it met on Thursday, and will next convene on Monday, when it is possible it could hear from an additional witness, according to two sources familiar with the matter.

As the investigation comes closer to its end, prosecutors are considering the historic nature of prosecuting a former president, which would be an unprecedented action, sources tell CNN. Other sources say the district attorney’s office is taking a moment to regroup after the events of the past week.

After Trump over the weekend predicted on his social media that he would be arrested on Tuesday, anticipation roared over the investigation and the prospect of an indictment. But then it seemed to ebb after the grand jury did not meet on Wednesday and convened to hear another matter on Thursday.

In essence, the former president helped create the expectation he would be indicted, then he and fellow Republicans used it to score political points against Bragg and Democrats.

Trump seized on the pause in grand jury action on Thursday to continue to rail against Bragg, claiming there was “total disarray in the Manhattan D.A.’s Office.”

In an overnight social media post on Friday, Trump escalated his rhetoric and raised the possibility of “potential death & destruction” if he is indicted, with the former president continuing to assert “NO Crime has been committed.”

Bragg is investigating Trump’s alleged role in a scheme to pay hush money to adult film star Stormy Daniels before the 2016 election to keep silent about an alleged affair with Trump a decade earlier. Trump has denied the affair.

Preparations continue on Centre Street

Law enforcement officials are preparing for the possibility of a decision from the grand jury next week but are still waiting to hear from the district attorney’s office.

The New York Police Department held a rehearsal on Wednesday for its posture if there are protests in downtown New York, although preparations are still underway, according to a law enforcement official.

There haven’t been any sizable protests this week despite Trump’s calls, or any known credible threat.

One law enforcement source familiar with security planning around the Manhattan DA’s Trump hush money case told CNN on Thursday that it is still unclear as to when, or if, an indictment could come.

Coincidentally, the sequel to the film “Joker” is filming in the area of the Manhattan courthouse where the grand jury meets. It is expected there will be scenes that include protests and cars on fire, according to a source familiar with the planning.

Bragg’s office debates bringing Cohen back

The district attorney’s office is trying to determine whether to call back Trump’s former lawyer and fixer, Michael Cohen, to refute the testimony provided earlier this week by lawyer Robert Costello — or to call an additional witness to buttress their case before the grand jurors consider a vote on whether to indict the former president, one source familiar with the investigation said.

Costello testified on Monday before the grand jury, at the request of Trump’s attorneys, in an effort to undercut the reliability of Cohen, a key witness for the prosecution. It’s unclear whether Costello’s testimony altered the district attorney’s strategy as he’s mulled whether to call an additional witness.

“Up until this point, the grand jury had only heard the prosecution’s witnesses, under questioning by prosecutors, with no input from defense counsel or potential defendants,” said Elie Honig, a former prosecutor and CNN senior legal analyst. “So Costello would have given the grand jury a defense perspective, for the first time.”

Costello told CNN his appearance before the grand jury Monday was, at times, contentious.

He said he was questioned by a prosecutor while seven other assistant district attorneys also sat inside the grand jury room. While grand jury proceedings are sealed, Costello claimed he challenged prosecutors about why he was only asked about six of the hundreds of documents he submitted and, at one point, he turned to the grand jury and told them they should demand to see all the documents. Costello says five or six jurors nodded in agreement with his statement.

“Without a doubt my testimony had an impact on the grand jury. I told the truth about Michael Cohen. I did not try to embarrass the DA’s office or Alvin Bragg,” Costello said.

Costello said he has not heard from the DA’s office since his appearance.

Following Costello’s testimony, Cohen claimed in an MSNBC interview that Costello made “false statements” about him to the grand jury and tried “to muddy the water as best as he possibly can.”

Trump hush money probe goes quiet after chaotic week