MPs have united to condemn plans to create official Brexit and Remain emojis as “divisive and dangerous”.

The new characters – dubbed Brexit Bulldog and Starry Blue – are part of plans by an Italian emoji firm to cash in on the Brexit debate.

A paid-for app download is due to be launched on Sunday, giving people the option to use the emojis to give their social-media profiles a Brexit “brand identity”. Brexit is one of the most used words in British social-media conversations and the developers believe that if this can be monetised, the proceeds could be enormous.

Brexit Bulldog sports a Churchillian cigar and bowler hat, exuding defiant belligerence. By contrast, Starry Blue has the yellow stars of the European flag for eyes and wears a French beret and a broad grin.

Negotiations are under way with software companies to install the emojis. Users could pay for them or gain access for free by completing a quiz about their politics. But MPs have attacked the company after plans for the “Brexiji” app were leaked to the all-party parliamentary group on new social media.

The European Collective – a group of pro-Brexit Conservative MPs –and the Remain Group – an umbrella organisation representing pro-EU MPs – both condemned the app as “making money out of politics”.

“Nobody who campaigned in the referendum wanted to give shadowy organisations the chance to exploit British voters,” the groups said in a joint statement. “Brexit is far too serious a matter for foolish jokes.”

A former employee of the firm behind the scheme, Riccardo Nicoletti, told the Observer the app developers had originally been motivated by “genuine concern” that emojis were being misinterpreted. “People have put the British flag and the EU flag in their profiles on Twitter and Instagram,” he said. “Then they have to use other things to make their point, like ‘heart’ or ‘poo’ or ‘clown face with blond hair’.” Most emojis are free, but the Italian firm believes that even if few voters are prepared to pay for the app, plenty of political campaign groups “will happily spend other people’s money to get an advantage”, Nicoletti said.

“You’ve got the Remainers, the Brexiters and the Russian trolls. Some senior managers believe there are enough fake accounts on Twitter alone to make it the break-out app of the year. Our focus groups also showed that there were people who would use the emoji because they just want someone to tell them what Brexit means.”

Government sources indicated that if the Gibraltar-based company pressed ahead with the launch, ministers might look at imposing a post-Brexit import tariff on emojis.

“I’m sure the social media companies will be watching this closely,” said Daly Best, the chairman of Youth Systems, a social media thinktank. “Political emojis could be a great way to restore trust in social media.”