Nokia will unveil its first Windows-based smartphones this quarter, arguing that there is room for an alternative to the products of big-hitters Apple and Google on the same day that Apple prepared to launch its latest iPhone.

Our belief is that there is a clear opportunity for an alternative ecosystem, chief executive Stephen Elop told a technology fair in Helsinki on Tuesday.

Nokia was expected to launch one handset late October at its annual Nokia World trade show in London but in a signal that more may be forthcoming, Elop talked of introducing products in the current quarter.

The world's largest phone maker by volume, left in the dust by Apple and Google, announced a high-risk new strategy at the start of the year to ditch its home-grown Symbian software for a deal with Microsoft.

The switch -- which Elop likened to jumping from a burning oil platform -- meant a tough eight-month changeover period during which investors fretted about the delay between the announcement and the first of its Windows smartphone models reaching the market.

Already struggling with falling sales and profits, Nokia has seen its shares halve since the announcement on worries it would lose so much market share before the new phones come out that it might never make up lost ground.

Meanwhile Apple is expected to unveil the new version of its iconic iPhone later on Tuesday.

Both Apple and Samsung outstripped Nokia in the smartphone market this year, ending its 15-year reign at the top of that market. Nokia's quarterly phone sales to end-June dropped 20 percent at a time when the market grew 10 percent [ID:nLDE76K01W]

Elop, who took over a year ago, last week unveiled a plan to cut 3,500 jobs in its second major restructuring in six months. The latest redundancies come on top of cost cut plans set out in April, which included laying off 4,000 staff.

Nokia shares were down 3.9 percent at 4.08 euros at 0956 GMT.

(Additional reporting by Ritsuko Ando; Editing by Sophie Walker)

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