An LNP campaign advertisement on a Brisbane billboard has been slammed by other political parties as being misleading and masquerading an "increasingly toxic" LNP reputation.

The ad first appeared on an electronic billboard at the intersection of Lytton and Wellington roads at East Brisbane in late December, encouraging residents to vote for LNP candidate Melina Morgan at the Morningside byelection on Saturday, January 20.

Team Quirk advertisement on Shaftson Avenue, East Brisbane.

The sign said, “Melina supports a 100% carbon neutral council”.

The billboard message was displayed in green and white with a yellow banner at the top, but the typical LNP colour was blue and Brisbane City Council colours were blue and gold.