Chris Martin says that Rihanna is 'the best singer of all time'

Coldplay frontman Chris Martin has declared Rihanna to be "the best singer of all time" ahead of her half-time show performance at the Super Bowl.

The 45-year-old vocalist declared himself to be a fan of the Umbrella singer, with whom he has performed on a number of occasions over the years.

Read more: Rita Ora reveals truth about her "feud" with Rihanna

Martin told The Zane Lowe Show — reported via Billboard — that a Rihanna concert is now a special occasion, given how rarely the star takes to the stage.

Her Super Bowl LVII half-time show will mark Rihanna's first live performance in more than five years.

Martin said: "It is rarer and rarer for her to just sing, which is what makes it even more special, and in a strange way, it shows that she really, really wants to do it. No one can make Rihanna do anything at this point."

Going even further in his assessment of her talents, the star said: "You have to be an idiot not to recognise that she’s the best singer of all time."

Read more: Gwyneth Paltrow talks post-divorce relationship with Chris Martin

Rihanna collaborated with Coldplay on the 2012 song Princess Of China and made a surprise appearance at several of the band's live shows that year, as well as at the closing ceremony of the Paralympics.

Martin said: "I’m very biased because I’m such a big Rihanna fan. I mean, I think she could just walk out in sweatpants and sing, and that would be just great."

Rihanna will provide the half-time entertainment at this year's Super Bowl clash between the Kansas City Chiefs and the Philadelphia Eagles, taking place at the State Farm Stadium in Glendale, Arizona.

Last year's half-time show was the first to be focused entirely around hip hop music and was headlined by Dr. Dre, Snoop Dogg, Eminem, Mary J. Blige, and Kendrick Lamar, with guest appearances by 50 Cent and Anderson .Paak.

Martin himself took on headliner duties with Coldplay for the Super Bowl in 2016, with Beyoncé and Bruno Mars making special appearances that year.

Watch: Rihanna teases her Super Bowl performance