Alicia Keys seeks Rosalía's help with Spanish pronunciation

The US-born R&B singer has linked up with Puerto Ricans Pedro Chapó and Farruko for the remix, in which she has to sing two rhyming couplets in Spanish, a language she speaks to a certain degree but does not consider herself fluent in.

She turned to Rosalía - fresh from the USA's huge Coachella festival, where Reggaeton artists with Spanish lyrics have performed in mainstream slots for the first time in history - to give her pronunciation lessons via Facetime.

Alicia has to sing: "Vamos pa' la playa, pa curarte el alma/Cierra la pantalla, abre la medalla." ('Let's go to the beach, to heal your soul/Shut down your screen and open your medallion').

The Spanish 'artist of the moment', who also launched a clothing range at budget streetwear chain Pull&Bear earlier this year, helped Alicia with musical aspects as well as giving her linguistic advice.

"Need my Spanish RIGHT so I had to hit my girl @Rosaliavt. Shout out to my beautiful sis! She helped me make sure I was 100% for Calma to shine with @pedrocapo and @farrukooficial!!! Watch the full video on my YouTube channel," Alicia tweeted afterwards.

Rosalía retweeted the message, adding the comment, "I helped a mi amiga @aliciakeys," with a series of heart-eyed emojis.

The remix of Calma has already notched up six million YouTube hits in just over a week.

Fans of both artists have now started clamouring for Rosalía and Alicia to release a record between them.

Photograph: Alicia Keys on Twitter (@aliciakeys)