Charli XCX fails to raise a smile as she leaves London pub hours before nemesis Taylor Swift's star-studded wedding celebration in New York

Despite starting off as friends, Charli XCX and 's relationship has deteriorated so much that they're said to have written diss tracks about each other.

So it came as no surprise to see Charli, 33, wasn't on the guestlist for Taylor's star-studded wedding celebration with that's taking place in the States this weekend. 

While the stars' mutual friends such as and Jack Antonoff have headed to New York for the festivities, Charli remained in London. 

On Thursday, the Brat singer looked sombre as she left a pub, keeping her head down and wearing shades despite it being dark out. 

Charli kept her ensemble simple, flashing a hint of her lace black bra beneath a white vest that she paired with wide legged jeans. 

She layered up with a leather bomber jacket and boosted her frame with a pair of black heels.  

Charli and Taylor's feud came to a head last year, thanks to Taylor's seemingly pointed words about Charli's 'coke habit' in the track which features on Taylor's new album, The Life Of A Showgirl. 

Taylor recently admitted her song, Actually Romantic, is about an 'adversarial relationship.'

Charli is close friends with The 1975 frontman , whom Taylor briefly dated in 2023, after she married his bandmate George Daniels this year. 

Sharing a strikingly similar title to Charli's 2018 track Everything Is Romantic, she sings: 'I heard you call me "Boring Barbie" when the coke's got you brave.' 

Many listeners interpreted it as a pointed jab the singer, who has openly referenced drug use in her own music. 

Taylor's lyrics include: 'High-fived my ex and then you said you're glad he ghosted me / Wrote me a song saying it makes you sick to see my face' - seemingly a reference to Charli's friendship with . 

She also hints that the singer in question is seemingly obsessed with her, adding: 'But it's actually sweet / All the time you've spent on me / It's honestly wild.'

The pair have known each other for years with Taylor bringing Charli out as a support act on her 2018 reputation tour. 

But, more recently, many have speculated there is growing bad blood between the pair after Charli, whose real name is Charlotte Emma Aitchison, has grown closer with Matty in recent years. 

Matty himself is now engaged to model Gabbriette Bechtel, a long-time friend of Charli who has previously appeared in her music videos. 

Taylor opened up about the song's lyrics in the album's accompanying film The Official Release Party of a Showgirl, saying: 'It's a love letter to someone who hates you. 

'There can be this moment where it's unveiled to you, through things that they do that are very overt. And, as I've gotten older, I've just started to be like, "Oh my God, you did so much with this." It's flattering.' 

She added: 'That is, wow, that is very, very sweet of you to think about me this much, even if it's negative. In my industry, attention is affection, and you've given me a whole lot of it.'

It comes after Charli was rumoured to have written a song about Swift called Sympathy Is A Knife which featured on her hit album Brat.

In the song, Charli sang: 'Don’t know if I’m spiralling/ One voice tells me that they laugh/ George says I’m just paranoid/ Don’t wanna see her backstage at my boyfriend’s show/ Fingers crossed behind my back/ I hope they break up real quick.' 

Taylor gave further clues about Actually Romantic's subject in an audio track-by-track breakdown of the new album for Amazon Music, in which she said: 'It's a song about realising that someone else has kind of had a one-sided, adversarial relationship with you that you didn’t know about.

'And all of a sudden they start doing too much and they start letting you know that actually, you’ve been living in their head rent-free and you had no idea.' 

During Taylor's 2018 Reputation stadium tour, Charli opened for the 14-time Grammy Award winner on more than 50 nights.

But the first hint of trouble seemed to brew the following year in 2019, as while speaking to Pitchfork, Charli said: 'As an artist, it kind of felt like I was getting up onstage and waving to 5-year-olds.'

She went on to say following the tour it made her decide to never open for anyone again.

Charli added: 'I've done so much of it, and it really cemented my status as this underdog character, I need to just own my own f***ing s*** finally.'

Following backlash, she later took to her social media to say her comments had been taken out of context, insisting: 'As I say in the article and have said many times before, I am extremely grateful to Taylor for inviting me to open for her.

'She's one of the biggest artists of my generation and the Reputation tour was one of the biggest tours in history.'

She said that, prior to the tour, she had been playing '18+ club shows' and performing for 'all ages' had been 'new to me'.