TV duo Ant and Dec have been subjected to a Twitter backlash following news that the forthcoming series of ITV's Red or Black, which the pair host, is to be sponsored by payday loan firm Wonga.
An online campaign led by the Labour MP for Walthamstow, Stella Creasy, is calling for the deal to be dropped.
She said the firm was using the duo's "good name to promote legal loan sharking".
The MP said: "They could show some leadership and say this is nothing to do with us and we aren't happy about it.
"I've been running a campaign for the last two-and-a-half years to get the cost of credit capped in the UK.
"Wonga are trading on the image of Ant and Dec as some of the nation's favourite TV presenters."
A spokesman for the Newcastle-born double act, said: "Ant and Dec are the presenters of Red or Black. As presenters, the sponsorship of the series has nothing to do with them. They are not Executive Producers of Red or Black."
Wonga's website says its loans carry a typical APR of 4,214%, although the lender points out borrowers pay the loans back in a much shorter time frame, usually less than a month.
Wonga.com, whose catchphrase is "straight-talking money", was criticised by the trading watchdog in May for using aggressive and misleading debt collection methods.
The industry generally has been criticised for giving people loans which turn out to be unaffordable, rolling over loans and charging interest rates running to several thousand per cent.
A spokeswoman for the firm said: "We're usually kept very busy building Europe's fastest growing technology business and making sure that at least nine out of ten customers continue recommending us, but sometimes we like to launch new, straight-talking sponsorships, too. If that gets a few people talking and tweeting, we welcome that."
This is not the first time the ITV game show has run into controversy.
TV bosses changed the format to give contestants "more control" over whether they win or lose after the first series of the skill-free show, where success was based on pure luck, ran into trouble over concerns it glamorised betting.
Officials from the Gambling Commission, which regulates the industry in the UK, met ITV bosses to discuss the show, which offered a £1m prize to contestants who chose between red or black.
ITV said the show will now see contestants "use their judgment and skill to battle it out to win big money prizes".
The first series was also the subject of controversy when it emerged the first jackpot went to a contestant who had been jailed for a violent attack and several other contestants were removed from further shows after investigations into their backgrounds.
An ITV spokeswoman said: "Wonga is a well known brand and the sponsorship of Red or Black is fully compliant with Ofcom regulations."