An array of mysterious billboards with the number 30 have popped up across the world, sparking speculation among fans that Adele may be about to release a much-anticipated new album.

Photos of the signs have been snapped across the world on various iconic landmarks in locations including Dubai, Ireland, France, Italy and the US.

There has been no official confirmation from the Grammy award-winning artist, but the number would fit with her previous pattern of naming albums after her age.

The 33-year-old singer’s thirtieth year also marked the age she separated from her ex-husband Simon Konecki.

A new record would be Adele’s fourth album and first in six years, following 2015’s record-breaking 25.

That record, which followed her 2011 record 21 and her debut 19 in 2008, broke the single-week US album sales record, went on to sell some 23 million copies in total, and also earned her two Grammys: Album of the Year and Best Pop Vocal Album.

Speculation that Adele would be releasing a new record has been rife on the internet over the last year.

Last October, Adele, who has largely stayed out of the spotlight, appeared as the host on US TV show Saturday Night Live.

It prompted speculation she was on the verge of releasing her new music at around the same time.

However, she revealed during the show that she was only on hosting duties, with singer-songwriter HER appearing as musical guest.

She referenced the rumours in her opening monologue, saying: “I know there’s been a lot of chatter about me just being the host. Like ‘Why isn’t she the musical guest?’ and stuff like that. And there’s a couple of reasons.

“My album’s not finished, and I’m also too scared to do both… I’d rather just put on some wigs… have a glass of wine or six and just see what happens.”

Meanwhile, rumours that the singer could release the record before Christmas were further fueled by a radio DJ named Mauler last week.

According to Billboard, Mauler sent out a tweet that was later deleted on Tuesday, which said, “New Adele. This week”.