Microsoft boss Steve Ballmer said he was confident the company’s new mobile phone operating system would help it claw back market share from rivals, days after Goldman Sachs downgraded its assessment of the firm’s stock.

The world’s largest software company will launch Windows Phone 7 in New York today, trying to recover ground lost to Apple’s iPhone, Research in Motion’s BlackBerry and Google’s Android mobile platform.

“We are excited to be able to launch Windows Phone 7. We think we have pretty unique ideas and a unique perspective,” he told a business conference in Madrid when asked if he thought the new operating system would help the firm make up for lost ground.

“I think our products will stand out compared to any others. We would not be launching the product if we did not feel good about its chances to do well.”

Investment bank Goldman Sachs last week downgraded its rating on Microsoft shares to “neutral” from “buy,” saying revenues would remain under pressure until the company gained a firmer foothold in smartphone and iPad-style computer tablets.

Mr Ballmer said Windows-based tablets would be on the market as soon as they are ready.

“You will see us to continue to push Windows into new formats and when there is news on the topic we will report it,” he said.

Technology website Neowin .net said sources close to Microsoft had hinted the company would use the launch of its new mobile phone operating system today to outline plans for a series of tablet-like devices running the Windows operating system.

According to market research firm Gartner, Microsoft’s share of the worldwide mobile operating system market will fall to 4.7 percent this year from 8.7 per cent last year.

In June, Microsoft killed the “Kin,” a line of mobile telephones aimed at young people it had unveiled just two months earlier.

The Wall Street Journal recently reported that Microsoft would today offer three Windows Phone 7 smartphones with handsets made by South Korea’s Samsung and LG Electronics and Taiwan’s HTC.