In a letter sent late Thursday to Airbus employees, Enders said that when he exercised stock options in November 2005, "there was no reason to believe it would be improper." The Associated Press obtained a copy of the letter Friday.

For more than a year, the French Financial Markets Authority, or AMF, has been investigating share sales between November 2005 and March 2006 by 21 top managers of European Aeronautic Defence & Space Co.

A preliminary report by French regulators leaked to the press on Wednesday suggests "massive insider trading" took place at EADS.

Problems with the A380 and the mid-range A350 came to light publicly in June 2006, sending EADS shares tumbling 26 percent in one day.

Enders sold 50,000 shares for a profit of 711,750 euros ($1 million), according to the AMF. Airbus Chief Noel Forgeard in March 2006 made a profit of 2.5 million euros ($3.2 million).

"To be clear to you all, I have never committed any insider trading, and I have not been accused of insider dealing by anyone, including the AMF," Enders wrote in the letter. "I categorically deny the allegations and insinuations in the press."

Associated Press Writer Tobias Schmidt contributed to this report.