Danish jewellery maker Pandora increased its operating profit by almost 40 percent in the first quarter, exceeding analysts' expectations, and raised its full-year sales forecast.

However, shares in the company fell, together with the main Copenhagen stock exchange index, as analysts noted higher than foreseen costs, while the revenue upgrade was anticipated and due to a strong U.S. dollar.

Pandora shares, which have risen 40 percent so far this year, were 0.5 percent lower at 701.50 crowns by 0740 GMT compared with a 1 percent fall of Nasdaq's C20 index.

"The sales growth is strong but the development in fixed costs is not good," analyst Jesper Christensen from Alm. Brand Bank said.

Costs for the quarter rose 35 percent to 2.3 billion Danish crowns ($346 million) as Pandora continued to open new stores and launch marketing campaigns. It also raised its capital expenditure forecast for the year.

The group now sees 2015 sales of more than 15 billion crowns, up from an earlier forecast of more than 14 billion crowns. The 2015 EBITDA (earnings before interest, tax, depreciation and amortisation) margin is still seen at around 37 percent.

"The strong growth in established markets such as the United States, the United Kingdom, Australia and Germany is especially positive," Sydbank analyst Soren Lontoft Hansen said.

The company entered into an alliance with Walt Disney last year to increase sales in the United States. It also launched online stores there after good experience with its UK online platform.

Operating profit rose to 1.24 billion Danish crowns from 887 million crowns a year earlier and above a forecast for 1.17 billion in a Reuters poll.

Former Scandinavian Tobacco Group chief Anders Colding Friis took over as chief executive from Alan Leighton last month.

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