Nokia has been on the receiving end of a US class action suit, which the Financial Times said is based on an assertion that the company misrepresented the benefits of a move to Windows Phone for its smartphone unit.

In a statement, the company said that it “is reviewing the allegations contained in the complaint and believes they are without merit.”

The suit alleges that as Nokia began launching devices to market, it “made false and misleading statements and engaged in a scheme to deceive the market.” Once the performance of its Windows Phone line became apparent, “the price of Nokia’s securities fell precipitously.”

The move comes shortly after the company had to go on the defensive at its annual general meeting, with Risto Siilasmaa (pictured), its new chairman, stating that its strategy will remain unchanged, despite criticism from investors.

While Nokia is currently in the middle of its transition to Windows Phone for its high-end devices, there is little sign that the company has generated much momentum as-yet.

Coupled with increased pressure on its mass-market devices business, the company is facing a challenging future, against a backdrop of increased concern from investors.

In its most recent results release, Stephen Elop, CEO of Nokia, said that there is a “clear sense of urgency to move our strategy forward even faster.”

Nokia has recently been on the receiving end of downgrades from the three big ratings agencies – Fitch Ratings, Moody’s and Standard & Poor’s.