One of South Carolina's biggest private employers and exporters is gearing up to expand again in a move that would ripple all the way to the Charleston waterfront.

Norbert Reithofer, chief executive officer of BMW AG, said Wednesday the German automaker is looking to increase production in the United States.

BMW's only U.S. assembly plant is in the Upstate, where Reithofer plans to visit next week to announce an expansion of "its commitment in the USA," according to an invitation to the March 28 event.

He's scheduled to be joined at the Spartanburg County factory by U.S. Secretary of Commerce Penny Pritzker and Gov. Nikki Haley, among other invited guests. The international event will be streamed live online starting around 1 p.m.

BMW Manufacturing Co. spokeswoman Sky Foster on Wednesday declined to comment about the announcement.

The Munich-based company opened its only North American assembly plant in Greer 20 years ago this fall. It turned out about 300,000 sport utility vehicles in Spartanburg County last year.

Many of those automobiles are hauled on rail cars to the Columbus Street Terminal in Charleston, making BMW one of biggest export customers at the Port of Charleston.

State Ports Authority chief executive officer Jim Newsome declined Wednesday to comment about BMW or its expansion announcement.

The luxury carmaker's Upstate plant is wrapping up a $900 million expansion announced two years ago designed to boost production to about 350,000 vehicles annually and increase the payroll to more than 8,000 workers.

Reithofer cited the 20th anniversary of the factory in his remarks Wednesday in Munich.

"Since 1994, we have more than quadrupled our sales in the U.S. ... The U.S. will stay a market with great potential for us. This is why we are evaluating the possibility of increasing capacity in the U.S.," he said.

Reithofer declined to comment on future production levels in Greer or whether BMW will roll out a new vehicle, the X7, according to news reports.

Friedrich Eichiner, the automaker's finance chief, also alluded to the likely expansion in South Carolina, according to a written transcript of his remarks Wednesday.

"We expanded production facilities for the X4 and the upcoming X6," he said. "Over the past 10 years, the plant has built around 2.5 million BMWs. We are also considering increasing the plant's capacity. Located in the world's largest premium market, it is a decisive factor in the success of the BMW Group."

Tyrone Richardson of The Post and Courier contributed to this report.