I googled it yesterday, and even though it didn't supply the sizes in ml, this site.....
http://www.onlineconversion.com/cooking_volume.htm
.....did give comparisons between spoon sizes and how they differ on each side of the Atlantic.
1 Teaspoon [UK] = 0.72057 Teaspoon [US]
1 Tablespoon [UK] = 0.9607599 Tablespoon [US]
1 Tablespoon [UK] = 4 Teaspoon [UK]
1 Tablespoon [US] = 3 Teaspoon [US]
1 Tablespoon [US] = 4.1633709 Teaspoon [UK]
So to state that you ejaculate 4 tablespoons [US] would goggle the eyes of most British guys as that would mean you're pumping out enough to fill more than 16 of our teaspoons :)