The president of Toyota, Akio Toyoda, apologized late Monday for the problems created by recalling 9 million cars worldwide.

Writing on his Japanese-language blog under the name "Morizo," Toyoda says the automaker will "take seriously, accept humbly, and respond sincerely to" complaints that Toyota has not taken the recalls seriously enough, according to the Wall Street Journal.

Toyoda also wrote he won't be participating in a 24-hour endurance race in Germany as previously planned. He had taken part in the ADAC Nurburgring 24-Hour race at least 3 times before, and Toyoda had said last June that he would continue to take part in races after becoming top executive.

Toyota has recalled nearly 9 million cars in the U.S., Europe, Asia and other regions following problems with sudden acceleration with some models, including the top-selling Prius. Sales in the U.S. have plunged, and Toyota has introduced incentives to try and jump-start sales.

Meanwhile, Toyota is disputing a Prius driver's account that his car accelerated on its own in a dramatic incident captured on video last week on a California highway. Toyota says the driver repeatedly pressed the brake and accelerator, which would defeat a system that can prevent unintended acceleration. The car reached speeds of up to 90 miles per hour before it stopped.