NEW YORK, JUNE 15 -- It's official: Donald Trump can't pay his bills.

The flamboyant tycoon, short of cash and unable to borrow more because of feuds among his lenders, failed today to make about $45 million in payments due on a bank loan and on junk bonds he issued to finance his Trump Castle Casino.

The missed deadline, which put Trump legally in default on his debt, marks the first time the publicity-conscious mogul has failed to make timely payments to bondholders who helped him finance his three Atlantic City casinos.

Although Trump still has a 10-day grace period to make good on the bonds before he can be taken to bankruptcy court, bankers and financial analysts said his failure to pay the interest and principal on the bonds has already complicated his financial plight and signals that his difficulties are likely to get worse before they get better.

In addition, Trump yesterday missed interest payments on a $35 million loan to Manufacturers Hanover Corp., but bankers said the default on the junk bonds was much more serious.

The defaults came after Trump and bank lenders failed to reach agreement on a refinancing plan that would have given Trump a $60 million cash infusion to pay bondholders and keep his real estate, airline, hotel and casino empire in operation.

According to one executive close to the deal, lenders are pushing Trump to bring in a new senior executive who could take over the management of Trump's operations.

One leading candidate for the job is Fred Zuckerman, vice president and treasurer of Chrysler Corp., who helped lead the automaker through its financial troubles earlier this decade. Zuckerman, who had no comment today, has said he plans to leave Chrysler by summer's end.

Prices of the junk bonds dropped on public markets today, where trading was suspended for several hours. Later in the day, Moody's Investors Service lowered its ratings on Trump's bonds and cited the missed payment as one reason for doing so.

Today's default, while a worrying sign, proves only that Trump is currently short of cash. It does not mean that his various businesses and properties, when sold, would not bring in enough money to cover his debts.

"The distinction that must be drawn is between being illiquid, meaning not having enough ready cash, and insolvent, which is not having the money at all," said James D. Grant, a veteran Trump-watcher and editor of a bond-market newsletter.

But Trump faces a serious risk that his approximately 50 bank lenders, to whom he owes about $2 billion, will be unable to work out a deal among themselves to refinance his operations.

Trump's four principal bankers -- New York giants Citicorp, Bankers Trust of New York Corp., Chase Manhattan Corp. and Manufacturers Hanover Corp. -- have been unable to persuade several dozen smaller banks to go along with a tentative agreement reached last weekend that would have provided Trump the additional $60 million in new loans and suspended interest payments on some of his old loans in return for various new forms of collateral.

The agreement, according to one of Trump's bankers, became "a moving target" as talks dragged on through the day today at the Trump Tower, Trump's Fifth Avenue headquarters and one of his few properties still making money. The confidential negotiations, which began late last month, have been so intense that Trump's chief representative, Stan Ross of the Los Angeles accounting firm Kenneth Leventhal & Co., has been getting only about four hours of sleep a night.

Trump had enough cash to make a $16.1 million interest payment due today on junk bonds floated by his Trump Plaza Casino, which is the only one of his three Atlantic City gambling palaces that is on firm financial footing.

He did not have enough to pay $20 million in interest due on two issues of Trump Castle bonds or to buy back about $22.7 million of Castle bonds as he had promised when he floated the securities.

"The Trump Organization announced today that it is in ongoing negotiations with its lenders to obtain additional financing and restructure certain of its outstanding debt," according to a brief statement issued by Trump. "Pending the outcome of such negotiations, certain principal and interest payments required to be made today {on the bonds} ... are not being made."

A Trump spokesman said the normally talkative developer would have no further comment.

Most of the bondholders hurt by today's default are institutions such as mutual funds and insurance companies, and investors who specialize in speculating in troubled securities. If Trump fails to make the payments by June 25 -- the end of the grace period -- bondholders can sue or can petition a federal judge to force into bankruptcy the company that Trump set up to finance the Castle casino.

Ultimately, the bondholders can seize the casino if Trump fails to make the payments, but analysts say it is unlikely that would get them all of their money back. Recent estimates put the value of the Castle at about $250 million. The outstanding debt on the property is $370 million.