When Sanford I. Weill was negotiating to buy Primerica Corp. in 1988, he conditioned the purchase on the financial-services company throwing in its Gulfstream jet as part of the deal.

Mr. Weill's most recent deal negotiations also hinged on a corporate jet -- only this time, his efforts appear to have run aground.

Mr. Weill's bid to retire early as chairman of Citigroup Inc. hit a wall in recent days when his board told him he couldn't continue using the corporate jet and receive other retirement perks, including security detail -- and Mr. Weill rebuffed an offer to buy out those portions of his contract, people familiar with the matter say.

The upshot: After a two-decade reign as one of Wall Street's premier deal makers, Mr. Weill has stumbled on one of the most important transactions of his career -- his own departure from the company he led.

The negotiations, which unfolded over the past week, reached a stalemate by the weekend, and the impasse wasn't broken Tuesday, when the board wrapped up a regularly scheduled meeting, these people say.

Mr. Weill, 72 years old, had been discussing his plans to launch a buyout fund for several months with colleagues within Citigroup, and with potential investors including Saudi Arabia's Prince Alwaleed bin Talal, one of Citigroup's largest investors and a longtime supporter of Mr. Weill, a Citigroup executive said.

A Citigroup spokeswoman said neither the company nor Mr. Weill would comment on the matter. A spokesman for Prince Alwaleed also declined to comment.

"It's a bit of a standoff over the contract," the Citigroup executive said. "If they can't come to an agreement about changing the contract, it's likely he'll just wait until April, when he's scheduled to retire."

The board was concerned in part about potentially unfavorable publicity about Mr. Weill's retirement package, after the controversy generated by the packages granted former Morgan Stanley Chief Executive Philip Purcell and former General Electric Co. Chairman and Chief Executive John F. Welch Jr., this executive said.

Earlier this month, Morgan Stanley disclosed that it had awarded exit pay of about $44 million to Mr. Purcell, who was forced out last month. The package also entitled him to collect $62.3 million in previously granted stock and option awards, plus other benefits, including $250,000 annually for life.

In 2002, details of Mr. Welch's retirement package spilled out in his divorce proceedings, becoming a symbol of corporate excess. Mr. Welch subsequently agreed to forgo part of his compensation package and refunded some costs to GE.

What bothered some Citigroup directors was the appearance of having Mr. Weill use Citigroup aircraft to do business for his private-equity fund, according to a person familiar with the matter. Mr. Weill's employment contract gives him access to Citigroup's fleet of planes, and a personal security detail, for life.

Mr. Weill was told: "If you're going to do your own business, then you ought to use your own equipment," one person familiar with the negotiations said. "It wouldn't look good."

Mr. Weill countered that his contract entitled him to use the plane, this person said. The directors, playing hardball with a chairman known for hardball negotiations, told Mr. Weill if he wanted to continue receiving such perks, he had to abide by the contract calling for him to remain chairman until the 2006 annual meeting in April.

There were indications Tuesday that news of Mr. Weill's efforts had rattled some investors. Citigroup's shares fell to $44.40, down 60 cents, or 1.3 percent, in 4 p.m. composite trading on the New York Stock Exchange.

Anton Schutz, president of Mendon Capital Advisors, who holds Citigroup shares in three portfolios he manages, said Mr. Weill's actions didn't undermine his confidence in Citigroup's shares. But he noted the irony of Mr. Weill's apparent eagerness to split from Citigroup.

"Here is a guy who demanded the ultimate loyalty" when he served as Citigroup's chief executive, Mr. Schutz noted, and frowned upon any stock sales by senior executives.

Since stepping down as chief executive in October 2003, Mr. Weill hasn't been involved in day-to-day management, confounding the predictions of some who expected that he wouldn't be able to resist the urge to meddle.

"I'm not surprised about Sandy itching to do something else," said Mr. Schutz. "For his entire career, he's been a mover and shaker. I expect he's been a little bored not moving and shaking."

Mr. Weill already has jumped one timetable he set for Citigroup investors. In July 2003, when he tapped Charles Prince to succeed him as chief executive, he indicated the transition would occur at year-end 2003. Two months later, explaining that there was "no real reason to drag out the process," he said he would step down Oct. 1.

If Mr. Weill opts to launch a buyout fund upon his scheduled retirement in April or before, he will have to work around a noncompetition clause in his retirement agreement. Citigroup's recent proxy statement doesn't make it clear whether the clause would allow for such a buyout venture when he retires, or whether Mr. Weill would have to negotiate permission from the board. It is also unclear whether use of the plane and other perks would continue to be an issue.

The imminent departure of Citigroup President Robert Willumstad, an operations executive, also was a factor in the board's negotiations with Mr. Weill, according to a person familiar with the matter. With the disappointing quarterly results announced Monday, the board didn't want the two Citigroup veterans with the most operations experience leaving the company at the same time.

Many people on Wall Street had assumed that when Mr. Weill finally left Citigroup, it would be to retire, not to launch an outside business. Mr. Weill will be 73 at the time of next year's annual meeting.