In fact, the Mass according to the missal of Paul the VI nowhere indicates that the priest should face any other way than the way he faced in the older missal, which, of course, was east. In fact, the rubrics in the new missal indicate that the priest should turn towards the people, to greet the people with the Dominus vobiscum, for example.

The custom of facing the people developed outside of the missal itself, and the older practice is has been discouraged for the most part, if not outright forbidden for public masses, by individual bishops. “Facing the people” has become virtually the universal practice in the novus ordo.

A priest acts in accord with the rubrics when he faces east.

Here is a good article on the matter.

Thanks & God bless