The demonstration, which will take place a day before Katsav is expected to be indicted by the Jerusalem Magistrates' Court, will be attended by female Knesset members and public figures.
The rally will be hosted by radio and television broadcaster Merav Michaeli and will be attended by MKs Shelly Yacimovich (Labor), Zahava Gal-On (Meretz) and Nadia Hilou (Labor).
The police did not boost their forces ahead of the demonstration, and only several dozens of police officers were expected to secure the event. The police reported that streets in Tel Aviv would not be closed.
MK Yacimovich said that "this demonstration is aimed, first and foremost, at supporting and strengthening complainants who have yet to recover from the shock of the plea bargain.
"It also calls on the attorney general to change his mind and provide victims with the elementary right to appear before the court and give their testimonies, and allow the court to make a decision. I expect both men and women to take part in the demonstration."
MK Hilou said that "this demonstration is aimed at expressing the public's disgust over the expected deal. I hope a message will be conveyed in the demonstration that the legal system is not acting with justice toward the complainants in this case.
"I call on the entire public to come out and express its disgust over this deal. I am not only appealing to the women's public, but to the entire Israeli society. I would like to also see men in this demonstration."
Meretz faction chairwoman Zahava Gal-On said that "there is an entire public in the State of Israel – both men and women – which refuses to see the battle in favor of sexual assault victims going 20 years backwards. Therefore, we are fighting so that all rapists stand trial. Even if we are talking about a former president, he must be punished.
She added, "The public which will arrive at the demonstration today will not allow anyone to shut women's mouths… If (Attorney General Menachem) Mazuz is incapable of taking responsibility, he should let someone else fulfill the required duty."
'We must take the law into our own hands'
Dorit Abramovich, spokesperson for the Women's Coalition, which includes 11 different organizations, told Ynet that "the women's intifada has begun. It is clear to us that the rule of law does not defend victims of sexual assault, and therefore it is time for us to take the law into our own hands."
According to Abramovich, women and victims of sexual assault are expected to arrive from across the country in order to unite and declare the start of their struggle.
She stressed that women would not wait for the State to defend them. "We are no longer interested in the State's honor and the government's honor. Our battle now is for the safety of every woman," Abramovich said.
"In his decision Mazuz proved all the things we have been saying all along – the State safeguards its senior members, and there is a policy of clear discrimination between sex criminals belonging to the governmental elite and the rest of the plain citizens," she added.
Sources in the legal system were also outraged by Mazuz's decision, asking, "How would the attorney general have acted if it were his own daughter?"
Amnon Meranda, Yael Branovsky, Aviram Zino and Avi Cohen contributed to the report