* CEO says new ranges will take longer to achieve targets
* Company has branched out into childrenswear, lingerie
* Mango competes with Inditex's Zara and H&M (Adds details, quotes)
By Robert Hetz
MADRID, July 10 (Reuters) - Spanish fashion retailer Mango has cut its revenue forecasts for the next four years because it will take longer than previously thought to meet sales targets for new clothing lines, its chief executive said on Thursday.
The company launched childrens' and lingerie ranges in 2013 and has introduced lines for teenagers and mature women this year, as part of a 10-year expansion strategy.
"In the past, we've been a little bit optimistic and now we've decided to apply more conservative criteria (to sales targets)," CEO Enric Casi told Reuters. "The new lines will take a couple of years to reach sales per square metre ratios similar to those of our traditional offerings."
Its previous revenues forecasts for 2014-2017 were too optimistic, particularly for 2017, he said.
The company, which is family owned and has stores in more than 100 countries, in a report last week cut its revenue forecast for 2017 by around a third to 3.27 billion euros ($4.5 billion), from the 4.97 billion forecast in the previous year's report.
"Business is going fine, but the new brands will take longer to get a following," Casi said.
Mango competes with Zara, another Spanish fashion chain which is owned by the world's largest clothing retailer Inditex , as well as with Swedish peer H&M.
Mango saw slower sales growth in 2013 after branching out into new lines like sportswear and lingerie, as well as childrens' wear. Revenue increased to 1.85 billion euros in 2013, falling short of the company's 1.98 billion euro forecast.
The retailer has implemented an aggressive expansion plan, targeting four new stores a week. Key to this 10-year strategy is developing a portfolio of brands for men, children and older women.
Analysts had expressed doubt whether the clothing chain, which uses celebrities such as model Kate Moss and actress Scarlett Johansson in its advertising, would be able to grow and adapt its structure to this umbrella brand. ($1 = 0.7331 euros) (Reporting by Robert Hetz; Writing by Sonya Dowsett; Editing by Susan Fenton)