The president and incoming chief executive of the giant U.S. defense contractor Lockheed Martin has resigned, after what the company said was his “close personal relationship with a subordinate employee.”

The Maryland-based company, in a statement Friday, said its board of directors asked for and received the resignation of Christopher Kubasik from his roles as vice chairman, president and chief operating officer. The statement said the resignation was sought after an ethics investigation confirmed the relationship.

No other details were disclosed. But the statement said the 51-year-old Kubasik's actions “violated the company's code of ethics and business practices.” The statement went on to say his actions did not affect the company's “operational or financial performance.”

Lockheed Martin is one of the world's largest defense contractors, with nearly 75 percent of its revenues coming from sales to the U.S. government.

A corporate statement for the second quarter of 2012 showed net company sales of $11.9 billion.