Image copyright PA Image caption Witness produced one top five single, Chained to the Rhythm, but follow-ups Bon Appetit and Swish Swish faltered

The boss of Capitol Records says he's had "tough conversations" with Katy Perry following disappointing sales of her latest album, Witness.

Perry released her fourth album last June but, despite appearances at Radio 1's Big Weekend and Glastonbury, it failed to catch on with fans.

It entered the UK charts at number six, after selling 16,153 copies. To date, it has sold less than 60,000.

All of Perry's previous albums sold more than 500,000 copies in the UK.

Her best-seller is Teenage Dream, which earned four platinum discs, representing sales in excess of 1.2 million.

"It's an interesting story," said Capitol Records' Steve Barnett. "I love her and have forged a great relationship with her."

He said the four-year gap between Perry's third and fourth albums had damaged fans' "engagement" with the star.

"And so you sit down and have tough conversations with her and management," he told Variety.

"As successful as you've been, you learn. Personally I've learned more from our mistakes than our successes and I believe our artists are in the same category as that."

Perry is currently in the middle of her Witness world tour, which has fared better than the album it's named after.

The lavish, fun-filled show made $28.1 million (£20.4 million) last year - despite the odd technical malfunction - and is set to hit the UK in June.

Perry will also make her debut as a judge on American Idol in March - and Barnett said she'd already started to plot a musical comeback.

"She has a plan, and we have a plan, and I feel good about it."

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