HUNTSVILLE, AL—A joint venture between Mazda and Toyota is altering its plans for a new assembly plant being built here.

Mazda Toyota Manufacturing will produce an entirely new Toyota sport-utility vehicle and a new Mazda crossover vehicle at the plant. The company previously planned to assemble Toyota Corolla cars at the plant. Toyota already makes the Corolla at its plant in Mississippi.

The change of plans for the Alabama factory is because of a changing market and increasing demand for light trucks and SUVs. Mazda Toyota plans to release details on the new vehicles later.

The $1.6 billion plant under construction in Huntsville is expected to employ as many as 4,000 people. Production is expected to begin in 2021.