Probably no one had thought that Taylor Swift’s recent “Cardigan” and Avril Lavigne’s “I’m With You” were similar enough to belong together in a medley before Yungblud did, but upon hearing his strings-lade mashup, the “Folklore” artist was swift with her approval.

Yungblud blended the two songs in a segment filmed for BBC Radio 1’s annual Live Lounge Month, accompanying himself on acoustic guitar and joined by a cellist and two violin players.

Retweeting Yungblud’s posting of the performance, Swift wrote, “WELL this took my breath away and I’m honored to hear Cardigan intertwined with the wonderful @AvrilLavigne’s masterpiece ‘I’m with you’. Bravo and thanks @yungblud!!”

Interestingly, Yungblud didn’t stick terribly close to the melody of either hit, transposing “Cardigan” to a more cheerful key, and ditching some of the minor chords from Lavigne’s song as well, coming up with an altogether more cheerful-sounding juxtaposition of the two otherwise more bittersweet songs.

Yungblud referred to the two singers as “my favourite girls” in his original tweet, writing, “CARDIGAN x IM WITH YOU …  covered my favourite girls @taylorswift13 n @AvrilLavigne for the @BBCR1 live lounge! go watch full vid on youtube and run up the coms with ‘[hearts]s’ show em you’re bhc! #yungbludscardigan.”

Swift has been a visitor to the Live Lounge herself before for some surprising covers, like Phil Collins’ “Can’t Stop Loving You” last year.

The native Brit also performed a song of his own, “Strawberry Lipstick.” “Playing the Live Lounge was always a massive dream of mine – I used to have the CDs as a kid,” he vowed ahead of the appearance. “To do it last year was so insane, but this time I have eight months of repressed energy and a whole lot of fire to get out. So bring your petrol!”