PARIS — Mobile satellite services operator Inmarsat on June 15 inaugurated its long-promised hand-held telephone, positioning it as a low-cost alternative in a global satellite-telephone market that Inmarsat Chief Executive Andrew Sukawaty said is growing at no more than 3 percent annually.

London-based Inmarsat, which for the past 10 years has watched certain of its market segments erode because of competition from Iridium and Globalstar of the United States, and Thuraya of United Arab Emirates, is making no claims about enlarging the market with its IsatPhone Pro.

In an interview, Sukawaty said the goal of the product is simply to take customers from Iridium, Globalstar and Thuraya, and prevent these companies from making more inroads into Inmarsat’s business.

Sukawaty conceded that the task might have been easier had the IsatPhone been on the market as scheduled in 2008. He said the commercial release was not delayed by Inmarsat’s 2006 decision to replace the phone’s designer, EMS Technologies of Norcross, Ga., with Sasken Communication Technologies of Bangalore, India.

Rather, he said, the delays were mainly caused by Inmarsat’s decision to add to the IsatPhone’s functionalities and in particular to use Inmarsat’s own technology rather than to purchase a license.

These decisions increased Inmarsat’s capital spending on the IsatPhone to around $100 million from the planned $65 million, and forced the delay in the commercial rollout.

The delays also gave Inmarsat’s competitors more time to prepare. Milpitas, Calif.-based Globalstar, whose current constellation of satellites has been providing limited service because of an onboard problem perhaps caused by radiation, has been contending with a loss of customers to McLean, Va.-based Iridium Communications.

But Globalstar plans to begin launching its second-generation satellites late this year.

Iridium, in addition to taking advantage of Globalstar’s degraded two-way voice service, has been able to maintain prices for its 9555 handset longer than it might have if Inmarsat’s IsatPhone had been in the market earlier. Iridium officials say there is sufficient profit margin in the current 9555 price levels to permit them to reduce prices if and when the Inmarsat product becomes a market threat.

“We would have preferred to be in the market earlier,” Sukawaty said.

The global satellite-handset market is difficult to quantify, but Inmarsat estimates the annual wholesale revenue at between $350 million and $400 million. Sukawaty said growth rates have slowed in the past couple of years, but Inmarsat continues to target a 10 percent market share, in revenue terms, by mid-2012.

Sukawaty declined to say how much Inmarsat has invested in supporting the early production run of IsatPhone units from Elkotech, a consumer-electronics manufacturer based in Central and Eastern Europe. He said that judging from preorders of the phones by Inmarsat’s distribution and service partners, the first production run will be sold out before the end of the year. He declined to specify how many phones had been ordered.

The IsatPhone will carry a list price of about $699, but Inmarsat says it has struck agreements with distributors that will bring prices down to between $500 and $600, with calling charges of less than $1 per minute. The service will use the three Inmarsat 4 satellites in geostationary orbit 36,000 kilometers over the equator. Positioned approximately 120 degrees apart, the satellites provide global coverage except for the polar regions, which are beyond the reach of geostationary-orbiting spacecraft.

Thuraya also uses geostationary-orbit satellites, but is focused on a 100-nation region centered in the Middle East and Africa.

Iridium and Globalstar use low-orbiting satellite constellations whose designs offer fully global service, including at the poles.

The IsatPhone is available worldwide as of June 15, but Inmarsat is placing special emphasis on certain regions that Sukawaty declined to name. He said nonetheless that Inmarsat views the North American market as less of a handset priority because of the position of Iridium there and the fact that Globalstar, once its voice service is fully restored with the new satellites, likely will try to win back customers there from Iridium. Similarly, he said, Thuraya is well-established in its home region of the Middle East.

Data on how many customers quit a satellite-phone service once their contract is up for renewal are unclear, Sukawaty said, especially since Globalstar’s voice-service difficulties have caused customer churn that might not have occurred otherwise. Inmarsat’s market studies show that satellite-phone owners, much like cell phone owners, change their equipment about every three years.

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