DETROIT (Reuters) - Ford Motor Co (>> Ford Motor Company) plans to introduce a new hybrid gasoline-electric car in late 2018 to compete against the best-selling Toyota Prius, two sources with knowledge of the company's plans told Reuters on Wednesday.

The compact car will be Ford's first "dedicated" hybrid - that is a vehicle designed to be marketed exclusively as a hybrid, rather than a variation of an existing gasoline model, such as the automaker's Fusion hybrid, the sources said. The as-yet-unnamed vehicle will be built just outside Detroit, .

The sources said Ford eventually could offer several different body styles of the new hybrid, as Toyota does with the Prius. There would be different versions of the car's gasoline-electric drivetrain, including a more expensive plug-in model that can be recharged from an electrical outlet.

The new Ford hybrid is expected to arrive as a 2019 model, roughly 21 years after the introduction of the original Prius in Japan. Toyota is planning to unveil its fourth-generation Prius late next year, the sources said.

Ford spokesman Chris Preuss on Wednesday said the company doesn't comment on speculation about future products.

Ford plans to build the new hybrid at its Wayne assembly plant in southeastern Michigan, at an annual rate of about 120,000, the sources said.

Some of the hybrid technology, including electric motors, controllers and batteries, will be adapted from Ford's current hybrid models, although the dedicated 2019 model is expected to provide better fuel economy and range than today's hybrids.

The 2019 model, which carries the internal code C240, will be built on Ford's new C2 global compact architecture, which also will underpin the next-generation Focus and Escape, the sources said.

Ford, like other major global automakers, has been investing heavily in hybrid technology to meet increasingly stringent emissions and fuel economy standards in North America, Europe and Asia. But consumer demand for hybrids hasn't come close to meeting the industry's sales projections.

Sales of the Chevrolet Volt, General Motors' (>> General Motors Company) widely advertised plug-in hybrid, have been just 10,635 vehicles through the first seven months of this year, down 9 percent from a year ago, despite heavy dealer discounts.

Sales of Ford's C-Max hybrid are down 29 percent in the first seven months, to 16,444. Sales of its Fusion hybrid are up 24 percent, to 31,092, but still only account for one in every six Fusions sold in the U.S.

Prius, which has been sold in North America since 2000, remains the leading hybrid in global markets. Its U.S. sales in the first seven months of this year are down 11 percent to 127,776. Last year, worldwide sales of the Prius topped 400,000.

Part of the success of Prius has been attributed to Toyota's efforts to build its "green" car into a branded family of different hybrid models, from the tiny Prius C hatchback to the van-like Prius V. Prices start at just under $20,000.

The Volt has been hampered by its higher sticker price. Even after a $5,000 price cut a year ago, the base model starts at just over $35,000, although Chevrolet dealers continue to offer discounts of up to $6,000 on that, as well as zero-interest financing and low lease rates.

In about a year, Chevrolet plans to introduce a redesigned, second-generation Volt with improved features and performance, as a 2016 model, the sources said.

(Reporting by Paul Lienert in Detroit; Editing by Martin Howell)

By Paul Lienert