LOUISVILLE, Ky. (AP) -- Toyota said Monday it is investing $1.3 billion to retool its sprawling factory in Georgetown, Kentucky, where the company's flagship Camry sedans are built.

No new factory jobs are being added, but Toyota says the upgrades amount to the biggest single investment ever at one of its existing plants in the United States. The retooling also will sustain the existing 8,200 jobs at Toyota's largest plant, where nearly one-fourth of all Toyota vehicles produced in North America are made, the automaker said.

"This major overhaul will enable the plant to stay flexible and competitive, further cementing our presence in Kentucky," said Wil James, president of the plant, which also assembles the Avalon and the Lexus ES 350.

The updates at the Kentucky plant are part of Toyota's plans to invest $10 billion in the United States over the next five years, said CEO Jim Lentz of Toyota Motor North America, in a news release.

President Donald Trump, in a paragraph added to Toyota's news release at the White House's request on Sunday night, praised the investment and said it is "further evidence that manufacturers are now confident that the economic climate has greatly improved under my administration." The paragraph cited the National Association of Manufacturers' first-quarter outlook survey. It found that 93.3 percent of manufacturers are somewhat or very positive about their company's outlook, a record high that's up from 77.8 percent in December.

But the Toyota investment has been in the works for years as it gears up for production of the revamped 2018 Camry, long the top-selling car in the U.S. Toyota has said the Camry's new underpinnings were designed four or five years ago, and the factory upgrade is needed to build the new car which goes on sale late in the summer. The Camry features a new exterior design, an upgraded interior and a new engine. The plant recently added more than 700 workers to support its launch.

"The (production) line itself is being retooled to accommodate this change," Toyota spokesman Scott Vazin said.

Toyota is betting that the changes will solidify Camry's top sales position as the top-selling vehicle in the U.S. that isn't a pickup truck. That dominance is under threat from the popularity of SUVs.