"Those words don't represent how I feel about this tragedy, and certainly don't represent the hearts of the people of BP -- many of whom live and work in the Gulf -- who are doing everything they can to make things right," Hayward said in the post.
"My first priority is doing all we can to restore the lives of the people of the Gulf region and their families -- to restore their lives, not mine."
In an interview with NBC on Sunday, Hayward had begun to offer an apology to Gulf residents "for the massive disruption it's caused to their lives."
He continued: "There's no one who wants this thing over more than I do, I'd like my life back."
The environmental disaster -- the worst in US history -- has badly damaged BP's reputation, with its shares sliding 2.13 percent Wednesday a day after plunging 13 percent, wiping 17.6 billion dollars off its market value.