THEY’RE the kings of operatic pop crossover, and she’s the queen. So it’s no surprise Il Divo and Katherine Jenkins should join forces. In fact, the only surprise is they haven’t done it before.

The multi-national quartet and the Welsh songstress head for the Echo arena in April as part of a UK tour.

Il Divo had the idea after a successful similar appearance with Barbra Streisand.

“We remembered that was a really good thing to do,” says the group’s Sebastien Izambard.

“So we asked Katherine if she’d be interested and she really liked the idea.

“She’s really delightful and has a great voice. So it’s going to be fun I think.”

The quartet will be performing songs from their new greatest hits album. They sat down with their record company, and also asked fans for input on Facebook and Twitter, before deciding what numbers to include.

The final running order features Il Divo favourites, and new numbers including Elvis’ Can’t Help Falling in Love and Whitney Houston’s I Will Always Love You.

It’s 10 years this year since the Paris-born singer and composer swapped his successful French pop career for the pop-op group put together by Simon Cowell.

“I look at the wrinkles!” he laughs. “And I look at my kids growing up and think wow, the time really goes quickly.”

Il Divo and Katherine Jenkins appear at the Echo Arena on April 10.