There are suggestions popular UK disc jockey DJ Fred Again could be playing a gig in Wellington.
Wellington City Council did not respond directly to RNZ's inquiry whether the artist was going to play a set.
It said it could not confirm anything until the artist-led announcement.
RNZ was told people have begun buying tickets to Wellington in anticipation of the announcement.
The spokesperson for the Homegrown festival, which was held over the weekend, told RNZ they were not allowed to comment.
It was rumoured while the other stages from the Homegrown festival last weekend had been taken down, the Park Stage had been left up for Fred Again to do a pop-up show this Friday or Saturday.
Organisers of the CubaDupa festival said they did not have any "secret acts or gigs planned", but were "looking forward to a magnificent weekend in the capital" nonetheless.
CupaDupa runs from midday Saturday until 9pm Sunday, "with no programming falling outside of these hours".
Fred Again posted a video of himself watching an old video of Jonah Lomu playing in an All Blacks game on his Instagram Story at 4pm on Tuesday.