It is both, it just depends on where it was viewed. It ran for two hours (120 minutes) with commercials when first broadcast on ITV in the UK. In the US, it runs on PBS commercial free (begathons notwithstanding <g>), and therefore runs 93 minutes.
It was 93 minutes long over here in Sweden too. But then it was also broadcasted on SVT, as in our public service network. So there could be no commercial breaks.