Carrie Underwood's scheduled performance at the Long Road Festival in Leicestershire, England, on Saturday (Sept. 8) has been scrapped due to illness.

A Facebook post shared on the festival's Twitter page indicates that Underwood has canceled several upcoming appearances in the United Kingdom, but does not reveal the nature of her illness.

"Our primary concern is her speedy recovery," the tweet reads.

Underwood was also set to play Radio 2 in London's Hyde Park, but a note at the BBC website reads similar to that posted across the Long Road Festival socials.

Aaron Watson will now headline Saturday night on the Rhinestone stage, with Danielle Bradbery extending her set to accommodate a gap. Watson was already on the lineup for Long Road. It's the festival's first year, and they boast more than 70 acts across five stages.

Taste of Country has reached out to Underwood's representatives for more information on the nature of her illness. She is currently pregnant with her second child, although it's not clear how far along she is. The baby will join 3-year-old Isaiah on the road in 2019 when Underwood begins the Cry Pretty 360 Tour.

Watch Carrie Underwood Talk About Her New Album

Many country music fans attending the Long Road Festival were understandably upset about Underwood's cancelation, although many look forward to seeing Watson, a Texan known for an energetic live show and easy rapport with fans. He is a more traditional country singer in the style of George Strait, which is a far cry from Underwood's more pop-friendly beats.

A note from UMG Nashville screenshotted on the Long Road Twitter page indicates that there were other appearances scheduled to promote her new Cry Pretty album, which drops in America on Sept. 14.

"She looks forward to resuming promotion for her new album, Cry Pretty, soon," it says. Underwood last played on Sept. 1 at the Tuckerville Festival in the Netherlands.

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