PARIS — GHL Acquisition Corp. (GHQ), which is trying to win its shareholders’ approval to purchase mobile satellite services provider Iridium, has sharply reduced the amount it will pay for Iridium in an 11th-hour bid to secure GHQ’s owners’ backing, GHQ and Iridium announced April 28.

Iridium also announced that it is unlikely to select a prime contractor for its second-generation satellite constellation before June, but is on track to complete the deal by this summer.

Iridium Chief Executive Matt Desch said the company is using competitor Globalstar’s tentative win of $574 million in credit guarantees from France’s Coface export credit agency as a spur to seek its own export credit agency support for Iridium Next, the company’s next-generation satellite constellation.

Iridium has estimated Iridium Next will cost around $2.7 billion. Bethesda, Md.-based Iridium is nearing the end of a review of bids from Lockheed Martin Commercial Space Systems of Newtown, Pa., and Thales Alenia Space of France and Italy to build Iridium Next.

Export credit aid would be more easily available to Iridium if it purchased both its satellites and their launches from a single nation. But Iridium and ThalesAlenia Space officials have said that even if the Franco-Italian company wins the business, integration of the Iridium satellites will be done in the United States to accommodate concerns by the U.S. government, which Iridium hopes will place piggyback instruments aboard at least some Iridium satellites.

Industry officials say that while France’s Coface appears to have been more active during the current credit crisis, the U.S. Export-Import Bank is capable of offering the same kind of loan guarantees for work done by U.S. companies.

“There seems to be an appetite for government sponsorship of industry,” Desch said of Coface’sGlobalstar guarantees. “I’d like to see if we could take advantage of that, too. It has opened up an opportunity we are going to continue to look into.”

GHQ of New York, created by investment bank Greenhill & Co. in early 2008 with $400 million in cash intended to find an acquisition, reached agreement with Iridium Holdings LLC in September on a deal that valued Iridium at $591 million including Iridium’s debt, which totaled $131 million at the time.

But the continuing financial crisis, which has made investors less inclined to part with cash and also has made alternative investments less expensive, forced the two companies to revise their deal.

Under the new arrangement, GHQ’s purchase values Iridium at $517.3 million, including Iridium’s debt of $145.8 million at Dec. 31. Iridium’s current owners will get $77 million in cash, the same as under the previous agreement, but $294.4 million of GHQ shares instead of $360 million.

GHQ said the aggregate payment to Iridium shareholders has been reduced by 15 percent.

In an April 29 conference call, GHQ Chief Executive Scott L. Bok said the terms “meaningfully reduced price” was agreed to only because of “lower equity market valuations” generally, and not because of any fresh assessment that Iridium’s business is of lesser value. “We think this transaction is a phenomenal opportunity” for GHQ shareholders, Bok said.

Greenhill & Co., which had previously purchased 2 million warrants in GHQ that it had purchased during GHQ’s initial stock offering in early 2008, agreed to forfeit this asset as part of the revised Iridium purchase agreement, GHQ said.

Iridium’s board of directors and its principal shareholders have accepted the new terms, and GHQ is scheduled to ask its shareholders for approval in the coming weeks, once the transaction receives U.S. regulatory approval.

GHQ needs at least 70 percent of its shareholders, not including those who are affiliated with Greenhill & Co., to vote for the transaction for it to close.

Desch said during the conference call that Iridium’s performance so far in 2009 suggests the company will increase its subscribers this year by 20 percent, and that overall company revenue will increase “in the low single-digit” range.

Iridium is in the midst of replacing its current generation of handheld satellite phones with newer models, a period during which the company is seeing lower handset sales as some customers and distributors wait for the new-generation gear to arrive.

But while hardware sales are down so far this year, the revenue generated by use of the Iridium system is increasing at “about the same level as subscribers,” Desch said. Iridium expects to report growth in operational earnings before interest, taxes, depreciation and amortization by 11 percent to 20 percent in 2009, to between $120 million and $130 million, Desch said.

Peter B. de Selding was the Paris bureau chief for SpaceNews.