satellite-phone venture, has missed a $90 million interest payment on $1.45 billion in outstanding debt.

Bermuda-registered Iridium said late on Thursday it now will have a 30-day grace period to hammer out a plan to restructure its debt.

On Wednesday, Iridium's general contractor and largest investor, Motorola Inc., warned that the project might have to be shut down and liquidated in bankruptcy law proceedings unless an agreement can be reached on debt restructuring. Such as restructuring could produce enormous losses for both investors and creditors.

The missed payment makes a Chapter 11 bankruptcy filing all the more likely.

The $5 billion satellite-telephone network was supposed to usher in a new age of wireless communications, but Iridium, which began operations last fall, has struggled to attract customers.

Iridium's stock, which has fallen more than 90 percent from its highs last year, was down 3.4 percent to $7 on the Nasdaq Stock Market on Friday.