Filmmaker Michael Bay has bumped up the release of the second Transformers sequel - it will hit movie theatres in 2011, a year earlier than planned.

Bay has announced that a script for Transformers 3 is complete and Megan Fox, Shia LaBeouf and their robot pals will be returning to the big screen sooner than fans had anticipated.

In a post on his website, which features a countdown to the new release date, the director writes, "Well it's official: We have a great Transformers 3 story. The release date is now July 1st 2011. Not 2012.

"Today is Day One. Currently I'm flying with writer Ehren Kruger to Rhode Island to talk to Hasbro about new characters."

Bay's post includes a cheeky swipe at Fox, who he clashed with over his filmmaking methods while shooting the last installment.

He adds, "P.S. Megan Fox, welcome back. I promise no alien robots will harm you in any way during the production of this motion picture.

"Please consult your physician when working under my direction because some side effects can occur, such as mild dizziness, intense nausea, suicidal tendencies, depression, minor chest hair growth, random internal hemorrhaging and inability to sleep.

"As some directors may be hazardous to your health, please consult your doctor to determine if this is right for you."

Both Bay and Fox will be hoping filming on Transformers 3 will be a lot less dramatic than the other two blockbusters - after the actress called her director "hopelessly awkward" during a 2009 interview, the crew of Transformers 2 lashed out at Fox in a collective message.

They wrote that the actress was "about as ungracious a person as you can ever fathom," adding, "She shows little interest in the crew members around her. We work to make her look good in every way, but she's absolutely never appreciative of anyone's hard work."