Technically, no, but it could be in more practical terms that the answer is yes.
There is a big diffference between subjects. It seems to be the case that scientists sometimes can go straight from BSc to PhD, whereas humanities students have to take the BA, MA, PhD route. I have a friend who at this second is applying for a PhD and he doesn't have a master's degree, he's a biologist. My ultimate goal is a PhD too, but I'm currently applying for a master's because PhDs are simply too competitive and underfunded in the humanities to possibly be considered without a master's (in my experience).
A few decades ago, skipping the master's was fairly common. It seems to be increasingly important, as they wish to see evidence that you have previous experience in research. My supervisor even snorted at the idea of (in humanities) applying for an MPhil without having an MA first.