Sen. Bob Menendez, his wife and two business associates all pleaded not guilty Wednesday in Manhattan federal court on bribery and extortion charges.

"We ask you to enter a plea of not guilty," Menendez's attorney, Seth Farber, said in court.

Menendez, D-N.J., was escorted into court by U.S. Marshals and took a seat at the defense table separate from his wife Nadine, who sat with her own lawyers. Menendez, in a gray pinstriped suit, slouched in his seat with his hands folded on his chest.

The senator was released on $100,000 bond and ordered to have no contact with his co-defendants besides his wife. He was also told to have no contact with Senate staff who have personal knowledge of the facts of the case unless accompanied by a lawyer.

Menendez was also ordered to turn over his personal passport and can only go on foreign trips in conjunction with official Senate business.

His wife, Nadine, was released on $250,000 bond secured by her house in Englewood Cliffs, New York, and was allowed to only travel in the New York-Washington corridor or to see family in Florida.

Menendez had already said he was innocent in fiery statements and in public remarks but this is when he will formally enter a not guilty plea and begin mounting a legal defense.

Menendez said the wads of cashed found in his jacket, his closet and in other parts of his home were the results of legitimate withdrawals he makes from his savings account, what he likened to "old fashioned" paranoia of the son of a Cuban immigrant worried about confiscation.

He did not address the gold bars and other forms of alleged bribery federal prosecutors said he took in exchange for wielding political influence on behalf of three associates.

One of them, Wael Hana -- who returned to the United States on Tuesday -- was formally placed under arrest and brought to court for an initial appearance.

Hana allegedly paid off Menendez, including giving a no-show job to the senator's wife, to ensure he could maintain a lucrative exclusive contract to provide halal meat to Egypt.

The other two businessmen charged in the case, Fred Daibes and Jose Uribe, are accused of paying Menendez in exchange for his help with separate criminal cases they faced, though U.S. Attorney Damian Williams said last week in his announcement of the charges neither the New Jersey Attorney General's office nor the U.S. Attorney in New Jersey succumbed to the pressure Menendez is alleged to have provided.

Menendez signaled Monday that he will remain in office despite pressure to resign from office.

Defiant as he delivered his first public remarks since the Sept. 22 indictment, Menendez spoke in Union Station, New Jersey, where he started his political career four decades ago. He took no questions from the press.

Menendez has temporarily stepped down from his influential post as chair of the Senate Foreign Relations Committee, Senate Majority Leader Chuck Schumer announced last week. Senate Democratic caucus rules state that any member who is charged with a felony must step aside from any leadership position.

Menendez has served in the Senate since 2006 and is up for reelection next year.

ABC News' Alexandra Hutzler and Allison Pecorin contributed to this report.