Marmite is beginning legal action against the British National Party after an image of a Marmite jar was used on a political broadcast without its permission, the company said.
The jar featured in the top left-hand corner of a video shown on the BNP's website.
The firm released a statement saying: "It has been brought to our attention that the British National Party has included a Marmite jar in a political broadcast shown currently online.
"We want to make it absolutely clear that Marmite did not give the BNP permission to use a pack shot of our product in their broadcast. Neither Marmite nor any other Unilever brand are aligned to any political party. We are currently initiating injunction proceedings against the BNP to remove the Marmite jar from the online broadcast and prevent them from using it in future."
The video now appears to have been removed from the BNP's website.
The Marmite jar appeared in the top left hand corner of the screen when party leader Nick Griffin was addressing viewers in the BNP's general election broadcast.
It provoked mixed opinion from contributors to a messageboard beneath the video, with several calling for the logo to be ditched but others praising it as a "brilliant" way to attract publicity.
Current advertising for Marmite is based around the slogan "love it or hate it" - an idea the BNP appears to have been trying to adopt. Marmite is owned by multinational company Unilever, whose other brands include PG Tips, Knorr and Vaseline.
Anti-BNP campaigners Hope not Hate said the reaction of BNP supporters calling for the jar's logo to be removed from the broadcast was virtually unprecedented, adding that contributions to the website are normally tightly controlled.
Spokesman Dan Hodges said: "In politics there is only one thing worse than being hated, and that's being mocked. Nick Griffin's Marmite broadcast has turned his party into a laughing stock, and it is quite clear his own members are not happy about it."