Katy Perry shocks fans as she accidentally reveals the team she'll be cheering on at the AFL Grand Final

Katy Perry has accidentally let slip the team she will be supporting at the 2024 AFL Grand Final on Saturday.

The US pop singer, 39, will be performing a set at the Brisbane Lions vs Sydney Swans game at the MCG this weekend.

On Thursday, following her appearance on Channel Seven's Sunrise, the Teenage Dream hitmaker stepped out and appeared to cheer for one of the coveted teams.

'Go Lions!' Perry said in a TikTok video, before trailing off and using random words to hide her slip-up.

'I mean, la-, mwah- swa...' she continued.

Lions fans were equally surprised and shocked by the gaffe.

'SHE'S A LIONS FAN,' one user commented.

'Katy & Lions for the win,' wrote another. 

The star of the pre-game entertainment insists she'll have no special allegiance towards Brisbane over the Sydney Swans when the two interstate teams battle it out at the MCG on Saturday. 

'You know, I'm Switzerland,' the performer told reporters at the MCG on Thursday.

'What I'm still trying to get over is that Melbourne has 10 teams, and they're not here!'

Perry will perform a string of her biggest hits to the 100,000-strong crowd including I Kissed a Girl with an Australian artist, rumoured to be Tina Arena, in one of her biggest shows since the 2015 Superbowl.

It will be her second performance at the stadium following her 2020 Women's Cricket World Cup appearance, which she said was a huge adrenaline rush.

'It'll be almost 10 years since I did something like this in the States, and to be able to do something like this again after so long, that doesn't always happen for an artist so I'm super stoked,' she said.

The American tried her hand at Aussie slang and AFL references in a press conference peppered with 'speccy' and 'granny' after a run on the grass in heels practising hand balls with AFLW stars.

'She was super bubbly,' Swans AFLW star Chloe Molloy told AAP.

'You never think you're going to rub shoulders with someone like pop icon Katy Perry.

'These are just the joys of football and how it brings people together.'

Homegrown pop singer and elite swimmer Cody Simpson will perform the national anthem on Saturday and likened his nerves to those on the starting blocks at the pool.

'It's an immense honour, it's probably the ideal way to be able to come back to the stage,' he said.

In other performances, Christine Anu will take to the stage alongside her daughter, and mad Swans fan, Zipporah for a special version of her most famous song My Island Home.

'It's so great that it gets to feature in such a significant event as the grand final between two of my favourite teams, so I've already won,' Anu said.

Up There Cazaly singer Mike Brady confirmed he'll once again perform his original hit, without a reference to late football legend Ron Barassi, in what he believes will be his 20th or 21st grand final appearance.

'I'm probably up for long service,' he joked.