Eminem has threatened to punch Lana Del Rey ''right in the face twice'' in a new rap.

The 42-year-old star makes the violent vow in a new 18-minute video for 'Shady Cxvpher', in which he warns he will strike the brunette beauty ''like Ray Rice'', the American footballer who was arrested in March and charged with third-degree aggravated assault after CCTV footage emerged of him appearing to punch his wife in the face.

In the new cipher, which is to support his new greatest hits album 'Shady XV', Eminem raps: ''But I may fight for gay rights, especially if the dyke is more of a knockout than Janay Rice/ Play nice? Bitch I'll punch Lana Del Rey right in the face twice, like Ray Rice in broad daylight in the plain sight of the elevator surveillance/ 'Til her head is banging on the railing, then celebrate with the Ravens.''

The shocking lyric comes less than a minute after a lyric about talk show host Anderson Cooper's sexuality.

Former Baltimore Ravens player Rice was arrested and charged in March and subsequently suspended from playing in the NFL indefinitely following the February incident, in which he is seen in the footage striking Janay Palmer in the face, knocking her unconscious.

Eminem's latest lyrics come after 29-year-old Lana said she ''f***ing loves'' him in an interview in 2012 in which she said she praised him for being ''the master of lyrics''.

The rapper has previously made a pop at female singers Mariah Carey, Britney Spears and Christina Aguilera in numerous tunes.