Pharrell Williams' Happy has become his third UK million-selling single within the space of just eight months.

The RCA-issued track, which is expected to return to No 1 this Sunday, reached seven figures this week, according to Official Charts Company data, and follows Daft Punk's Get Lucky and Robin Thicke's Blurred Lines (also featuring TI) all reaching the same landmark in 2013.

The achievement makes Williams only the third act in history after The Beatles and Rihanna to be part of ...