Image copyright Getty Images Image caption US rap star Kendrick Lamar will headline on Saturday (Reading) and Sunday (Leeds)

The boss of Reading and Leeds festivals has defended this year's line-up after some fans dismissed it as "incredibly underwhelming" and the "worst ever".

Headliners include Kendrick Lamar and Fall Out Boy, alongside the likes of Dua Lipa, rapper J Hus and Wolf Alice.

Some ticket-holders complained that the bill strayed too far from the event's rock roots.

"The key thing about any festival is that you don't stand still," Melvin Benn said. "I'm very clear on that."

He told BBC News: "You can't keep drumming up the same acts and expect people to continue to come and see them.

"Festivals have to be a reflection of what the public are listening to."

A second wave of artists was announced on Friday, featuring a higher volume of guitar bands, including Slaves, The Horrors, The Vaccines and The Kooks, alongside the likes of Kate Nash and hip-hop star Travis Scott.

Kings of Leon are the third headliners, while other confirmed acts include Skepta, Wolf Alice and Courteeners.

Some said the new line-up additions were an improvement.

Benn shrugged off the criticism, saying: "The ticket sales tell me that we're doing the right thing."

The 62-year-old, who also oversees events like Latitude, Wireless and the V Festival, also addressed the issue of gender balance at UK festivals.

The topic has been a cause for concern for the music industry since 2015, when a blogger created an embarrassing mock-up of the Reading and Leeds up poster with all the male performers removed. Only nine female acts remained.

On Monday, the PRS Foundation will announce that 45 festivals have pledged to work toward achieving a 50/50 gender balance by 2022 - covering music line-ups, conferences and commissions.

Benn, whose festivals have yet to sign up to the initiative, expressed doubts about the plan.

Image copyright Getty Images Image caption Wolf Alice are among the female-fronted bands on this year's Reading & Leeds line-up

"Is that the right way to go about it - to say it's got to be 50/50? I don't know that it is," he said.

Instead, he has launched a project called ReBalance, which will provide 36 female artists with one week's studio recording time over the next three years.

The aim is to "create a bigger pool of female acts" so that festivals have a "greater choice" when it comes to booking their line-ups.

"So actually, I do support the principle of it [gender equality]. I've chosen a slightly different way to go about it, but with the same principal aim."

The line-up for Reading and Leeds seems pretty diverse. What was the thinking behind that?

Melvin Benn: I don't think I'm very far away from what the essence of Reading and Leeds has always been, which is that it's a rock 'n' roll festival. But I guess my interpretation of rock 'n' roll might extend a little beyond guitar music - and that's the key here.

The fact that people are slightly surprised at Kendrick headlining is a bit of a shock to me.

Especially after Eminem headlined last year.

And Public Enemy were a headliner in the '90s. We've had Cypress Hill, too. It's always been the case that we've had that along with the old rock stars.

I think people were a little shocked [about Kendrick] to start with and now they're realising it's an incredible booking.

Image caption Many people hoped 2014 headliners Arctic Monkeys would return this year

What does his booking say about the future of the festival?

For me, it's just a clear demonstration that we are a reflection of what people are listening to. I was looking at, for instance, the Official Streaming Top 50 and the Official UK Radio Play Top 50, and there isn't a single guitar band in any one of those.

But actually, a significant amount of those songs have got songwriting skill and attitude at the heart of what they're writing and performing. And that's what rock 'n' roll is - it's songwriting and attitude.

One of the other criticisms was that acts like Fall Out Boy and Kings Of Leon could have headlined Reading 10 years ago. Are there any newer acts coming through who could take those slots?

It is a poisoned chalice, in a way, but I'd absolutely love to see Wolf Alice come through. And there's no reason they won't - because four or five albums in, I'd have thought Wolf Alice would be at that point. Are they at that point after two albums? Not quite, but they're certainly strong enough to headline the Radio 1 stage.

In four or five years' time, they'll be knocking at the door.

There were strong rumours that Arctic Monkeys would headline one of the nights. Were they ever in contention?

Not really. The Arctic Monkeys have headlined Reading and Leeds twice before so they're an act we're always talking to. Was it ever likely for this year? No, it wasn't. They've got their own plans.

You sort of know when someone's around and wanting to play, and it wasn't clear to us that they wanted to play, so we didn't push too hard.

Who are you most looking forward to on the line-up?

Kings Of Leon are one of my favourite guitar bands. I adore them.

And I don't want to feed the frenzy of the nay-sayers but it'd be difficult for me not to talk about Travis Scott. As a live act, this guy's incredible. He's was penultimate at Wireless last year - and there's no point in me pretending anything other, it was one of the most rock 'n' roll sets I've ever seen in my entire life. So Travis is very high on my list.

Courteeners at Benicassim last year was one of the most intense sets I've ever seen. They weren't headlining, but it was a headlining show that they put on. From that point on, I was like, these guys have got to be high up at Reading and Leeds.

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