In a 39-page indictment, federal prosecutors on Friday accused Robert Menendez, the powerful New Jersey senator and Democratic chairman of the Senate Foreign Relations Committee, of accepting bribes that included a luxury car, expensive exercise machines, mortgage payments, bars of gold bullion and more than $500,000 in cash.

In exchange for the bribes, Mr. Menendez wielded his power to increase U.S. assistance to Egypt and do favors for New Jersey businessmen, prosecutors said.

The indictment also names Mr. Menendez’s wife, Nadine Menendez, and three businessmen: Fred Daibes, a prominent New Jersey builder; Wael Hana, the founder of a halal meat certification company with headquarters in New Jersey; and Jose Uribe, a former insurance agent from Union City, N.J., who worked in the trucking industry.

All five defendants have been charged with conspiracy to commit bribery and conspiracy to commit honest services fraud. The senator and his wife were also charged with conspiracy to commit extortion under the color of official right, meaning that they leveraged Mr. Menendez’s role as a U.S. senator to force someone to give them something of value.

Mr. Menendez has maintained his innocence, accusing the Manhattan federal prosecutors who brought the case of misrepresenting routine congressional work. Lawyers for Ms. Menendez, Mr. Hana and Mr. Daibes have also denied the charges. A representative for Mr. Uribe could not immediately be reached for comment on Friday.

Here are four takeaways from the indictment:

Mr. Menendez met Mr. Hana, an American-Egyptian businessman who had relationships with top intelligence and military officials in Egypt, in early 2018, according to the indictment. Ms. Menendez, then Nadine Arslanian, was longtime friends with Mr. Hana and was eager to introduce him to Mr. Menendez, whom she had recently begun dating.

In the months and years that followed, prosecutors said, Ms. Menendez and Mr. Hana arranged a series of meetings for Mr. Menendez with Egyptian officials, who made various requests of the senator. In one text to an Egyptian general, Mr. Hana referred to Mr. Menendez as “our man.”

The group carried out an agreement in which Mr. Menendez would use his position to facilitate military equipment sales and financing to Egypt and, in exchange, Mr. Hana would put Ms. Menendez on his company’s payroll for a low- or no-show job, the indictment says.

At one point in 2018, prosecutors said, Mr. Menendez texted “highly sensitive” information from the State Department about employees at the U.S. Embassy in Cairo to Ms. Menendez. She forwarded it to Mr. Hana, who forwarded it to an Egyptian government official.

Mr. Menendez also ghostwrote a lobbying letter from an Egyptian official in 2018 asking U.S. senators to release a hold on $300 million in aid, prosecutors said.

Prosecutors noted that, at the time, the United States had been withholding additional aid money until Egypt was able to prove it had made improvements on human rights issues.

The indictment quotes text messages from Ms. Menendez bragging about the senator’s influence. In March 2020, Ms. Menendez texted an Egyptian official, “anytime you need anything you have my number and we will make everything happen.”

In 2018, Mr. Hana’s company, IS EG Halal Certified Inc., had little to no revenue, prosecutors said, and Ms. Menendez began to complain to her husband and others that she was not being paid. She caused at least one of Mr. Hana’s associates to believe that Mr. Menendez would stop working to help Mr. Hana and the Egyptian government unless Mr. Hana paid her, the indictment says.

In the spring of 2019, the Egyptian government granted Mr. Hana’s business a monopoly on certifying U.S. food exports to Egypt as compliant with halal standards, even though the company had no experience with such certification, the indictment says. The next day, Ms. Menendez texted Mr. Hana: “Seems like halal went through. It might be a fantastic 2019 all the way around.”

The monopoly resulted in increased costs for U.S. meat suppliers, which prompted the United States Department of Agriculture to ask Egyptian officials to reconsider their decision. Two days after a meeting in which Mr. Hana asked for Mr. Menendez’s help in countering the U.S.D.A.’s objections, Mr. Menendez personally called a “high-level” U.S.D.A. official and insisted that the agency stop opposing the monopoly, the indictment says. The official did not reverse his stance, but Mr. Hana’s company kept its monopoly.

About two months later, Mr. Hana’s company paid Ms. Menendez $23,000 to bring her mortgage payments up to date. When it was suggested to Ms. Menendez that Mr. Hana might be taken aback by the amount needed for the mortgage, she boasted that her actions would eventually make Mr. Hana “more powerful than the president of Egypt.”

Still, Ms. Menendez believed she had not been paid all of the money she was owed for helping Mr. Hana’s company, the indictment says. She texted Mr. Menendez, “I am soooooo upset,” and asked whether she should text Mr. Hana’s associate, Mr. Daibes, to complain, but the senator replied, “No, you should not text or email.” Ms. Menendez then called Mr. Daibes, and Mr. Hana’s company sent $10,000 to a consulting firm Ms. Menendez had founded and often used to receive bribes, according to the indictment.

In exchange for cash, furniture and gold bars, Mr. Menendez interfered with criminal proceedings on behalf of two New Jersey businessmen, one of whom was a longtime fund-raiser for the senator, the indictment says.

Prosecutors said that in 2019, Mr. Uribe, who had previously been convicted of fraud, and Mr. Hana asked Mr. Menendez to intervene in the criminal prosecution of one of Mr. Uribe’s business associates. They offered to buy a new Mercedes-Benz convertible worth more than $60,000 for Ms. Menendez, who had recently been in a car accident that had left her without a car.

Mr. Menendez pressured a senior prosecutor at the New Jersey attorney general’s office, who was supervising the case, to resolve it in the defendant’s favor. The official thought the request was inappropriate and did not agree to intervene, according to the indictment; Mr. Uribe’s associate ultimately received a plea deal with no jail time.

A few days after Mr. Menendez called the prosecutor, Ms. Menendez texted Mr. Hana: “All is GREAT! I’m so excited to get a car next week.” She met Mr. Uribe in a parking lot of a restaurant, where he gave her about $15,000 in cash, the indictment says. She made the down payment on the new Mercedes the next day. After the purchase, Mr. Uribe texted her, “are you happy?,” to which she responded, “I will never forget this.”

The indictment says that Mr. Menendez also agreed to try to influence the federal prosecution of Mr. Daibes, who had raised money for him, including by recommending that President Biden nominate a particular lawyer, Philip R. Sellinger, to be U.S. attorney for New Jersey because the senator believed he could influence Mr. Sellinger’s handling of the prosecution.

At one point during the period from late 2020 to early 2022 in which Mr. Menendez was seeking to interfere in Mr. Daibes’s case, Mr. Menendez and Ms. Menendez were picked up at the airport after a trip to Egypt by Mr. Daibes’s driver. The next day, the senator typed in an internet search, “how much is one kilo of gold worth.” An F.B.I. search of the couple’s home last year found multiple gold bars that prosecutors said were given to them by Mr. Daibes, along with cash and furniture.

The New Jersey U.S. attorney’s office did not bend to the pressure campaign, the indictment said. Mr. Daibes pleaded guilty in April 2022.

This is not the first time Mr. Menendez has been accused of corruption. In 2015, federal prosecutors in New Jersey charged the senator with bribery and accused him of performing political favors for a wealthy eye doctor in exchange for lavish gifts worth close to $1 million, including vacations to the Caribbean and campaign contributions. The trial ended in a hung jury in November 2017, and the judge later acquitted Mr. Menendez of several charges. The Justice Department dismissed the others.

During that case, Democrats largely rallied around Mr. Menendez, whose replacement would have been chosen by Chris Christie, who was then the Republican governor. In contrast, by Saturday afternoon, nearly every major Democratic figure in New Jersey had called on Mr. Menendez to resign, including Gov. Philip D. Murphy, senior members of Congress and influential state and county party chairmen.

When the indictment was unsealed, Mr. Menendez already had a Democratic primary opponent, Kyle Jasey, a real estate lender and first-time candidate who called the indictment an “embarrassment for our state.” Another New Jersey congressman, Andy Kim, declared his candidacy on social media Saturday afternoon.

Mr. Menendez’s colleagues in the Senate accepted his temporary resignation as chairman of the Foreign Relations Committee, but they did not ask him to leave office.

Nicholas Fandos contributed reporting.