The One Direction star will be the sketch show's musical guest when comedian Jimmy Fallon returns to host the programme on 15 April (17).

Styles previously appeared on Saturday Night Live when his boy band One Direction was the musical guest three separate times in 2012, 2013, and 2014.

Fallon earned his big break as an SNL regular before becoming an actor and late night TV host.

The news of his latest appearance on SNL comes just three days after Styles teased that something is coming on 7 April (17), prompting experts to believe he's ready to debut his first solo track.

In a mysterious TV ad, which aired in the U.K. on Saturday (25Mar17), the 23-year-old is seen soaking wet walking towards a door with light behind it. As his face comes into view, 'April 7th' flashes on a black screen.

Before the ad aired, Harry posted three blank white squares on Instagram, his first posts on the social media website in months. The announcement comes two years to the day that Zayn Malik left One Direction and on the same day his bandmate Liam Payne confirmed he had become a father for the first time - his girlfriend, former Girls Aloud star Cheryl, welcomed a baby boy last week (22Mar17).

Meanwhile, Harry is also gearing up for his movie debut later this year (17) in director Christopher Nolan's war film Dunkirk. The historical feature, starring Cillian Murphy, Kenneth Branagh, and Tom Hardy, hits cinemas in July (17).