by RadarOnline.com Staff
Who knew Robert Pattinson had such a potty mouth?!!
The Twilight hunk dropped the F bomb live on stage Sunday at the MTV Movie Awards and you can see it right here on RadarOnline.com.
Pattinson was in quite the mood for shocking it seems -- starting off by smooching Taylor Lautner then launching into a bordering-on vulgar speech about his Water For Elephants co-star Reese Witherspoon.
Detailing all his awkward moments on camera with the recently married actress - he's played her son and her lover - he rounded-up his speech by dropping the F bomb before stating that it's not a bad thing to have "sexual chemistry" with your mom.