UNITED NATIONS – Amid signs of a power struggle inside the higher echelons of the United Nations, a longtime aide and close friend of Mr. Annan resigned from his staff last week, in addition to his spokesman.

Elisabeth Lindenmayer, an assistant secretary-general and a deputy chief-of-staff who was at Mr. Annan’s side for over a decade, resigned last week and cleared out her office yesterday after what was described by aides as mounting pressure from the new chief-of-staff, Mark Malloch Brown.

Mr. Annan’s chief spokesman, Fred Eckhard, also offered his resignation in a personal letter, but the secretary-general had not yet decided yesterday whether or not to accept it. Mr. Eckhard said in his resignation letter that he would be willing to stay in his job until the end of Mr. Annan’s term, December 2006, if that is what the secretary-general wishes, said one official who described the letter to The New York Sun.

According to three sources who requested not to be quoted by name, Ms. Lindenmayer’s resignation came as a result of Mr. Malloch Brown’s effort to place his own confidantes in Mr. Annan’s immediate circles. Her post as Mr. Annan’s personal gate-keeper made her one of his closest advisers, with the power to determine who got to see him and who got left out in the cold.

One insider told the Sun that while Mr. Malloch Brown’s move was to be expected in the context of the new “palace politics,” it was also part of a trend that left Mr. Annan without some trusted friends and familiar faces. The source added, however, that after realizing the scope of the oil-for-food scandal, Mr. Annan decided that revamping the U.N.’s management was necessary for his legacy.

Ms. Lindenmayer was an “extremely valuable and hard working” member of the team, the undersecretary-general for communication, Shashi Tharoor, told the Sun, adding that he was “sorry to see her go.”

Last March, Ms. Lindenmayer was promoted to the position of assistant secretary-general, but even before that she had been in charge of determining Mr. Annan’s schedule and appointments, and set many of his daily priorities. The position of deputy chief-of-staff under Mr. Malloch Brown’s predecessor, Iqbal Riza, who retired in December at the beginning of the U.N. shakeup, gained even more responsibilities, including the important post of chief of protocol.

Ms. Lindenmayer had been at Mr. Annan’s side for long before that however, as his personal assistant and trusted and loyal aide. A French national who was born in Burkina Faso, or Upper Volta at the time, she often spoke glowingly of her boss in what at times sounded like near mythical terms.

“It’s very African to believe in symbols, in things that you don’t see, in the unquantifiable,” she told the New Yorker magazine last year, describing Mr. Annan’s style. “He asks us what we think, listens, is silent and thinks, and then he announces clear decisions,” she told another interviewer, again describing Mr. Annan’s management style as “African.”

Ms. Lindenmayer’s biography on the U.N. Web site offers this fact from her career: “In the aftermath of the 1991 Gulf War, she traveled to Baghdad and Vienna as part of the United Nations team involved in negotiations with the Government of Iraq for the establishment of the oil-for-food program.”

According to one insider, a recent “whispering campaign” against her management style, accusing her of not being able to work well with others, angered her and she decided suddenly to quit. Several sources told the Sun that the move took them by surprise.

Mr. Eckhard was said by a close confidante to have wanted to retire for a while, but out of loyalty to Mr. Annan, he decided to “stick it out.” However, realizing that part of Mr. Malloch Brown’s attempt to change the U.N.’s environment had to do with the need to reshape the way the message is being conveyed, he decided to offer his resignation once again. “My communication with Mr. Annan is private,” Mr. Eckhard told the Sun yesterday, refusing to comment on the resignation letter. Mr. Malloch Brown did not return a call to his office.

Separately, Mr. Eckhard said yesterday that Mr. Annan suspended with pay the two officials named in Paul Volcker’s oil-for-food report last week: the head of the program, Benon Sevan, and the head of the Security Council Affairs Division, Joseph Stephanides.

“Suspension is the beginning of a disciplinary process,” Mr. Eckhard said. “It means that they should not come onto the premises here unless it’s in connection with summoning their defense, which they have 14 days to present in writing.” He added however that the two will continue to be paid. Mr. Sevan has been retained as a U.N. employee after his retirement for the symbolic salary of $1 a year.