The crossover, which already has a polarizing bulky rear-end design, will be offered as a two-door with a droptop, company officials confirm.

Nissan showed the convertible to dealers at a meeting in Las Vegas this month. It is not clear when retailers will receive it, but it is likely to arrive in 2011.

One Nissan retailer, who asked not to be identified, commented that the design is "kind of unusual." He added: "It actually looks better with the top down than up."

Brian Carolin, Nissan North America Inc.'s senior vice president for sales and marketing, said the convertible is intended as an image vehicle for the Nissan brand.

"It's not going to be a volume car," Carolin said. "But there's a degree of bravery for us to bring out a car like that right now. It will surprise a lot of people."

Nissan has sold 34,141 Muranos through July, up 2 percent from a year before. The vehicle is the largest of Nissan's three crossovers, including the Rogue and a smaller Juke that goes on sale late this year.

Whether the Murano warrants a label as the first convertible crossover will depend on the industry's sometimes murky definitions.

Chrysler introduced a convertible version of its small PT Cruiser retro wagon in 2005. But the Nissan Murano is a larger vehicle that is less a wagon than an SUV. The Murano is more than 6 inches taller than the PT Cruiser and almost 20 inches longer.

Production of the PT Cruiser ended in July.