Burger King has offered its rival McDonald's the chance to mark this year's International Peace Day by creating a "McWhopper" burger together.
The mashup of Burger King’s Whopper and McDonald’s Big Mac would be created with ingredients from each chain to raise awareness of the day of global unity on Sept. 21.
Burger King proposes to create a purpose-built restaurant in Atlanta, halfway between the chains’ headquarters.
According to Fernando Machado, senior vice president for global brand management at Burger King, "Our proposal is designed to generate the most attention and awareness possible for Peace Day and the work of the nonprofit organization Peace One Day."
"We’re being completely transparent with our approach because we want them to take this seriously. It would be amazing if McDonald’s agrees to do this. Let’s make history and generate a lot of noise around Peace Day."
"If they say no, we’ll hopefully have, at the very least, raised much-needed financial support and consciousness for the great cause that is Peace One Day. And both are well worth the effort."
McDonald's CEO Steve Easterbrook issued a lukewarm response on the company's Facebook page this morning.
"We love the intention but think our two brands could do something bigger to make a difference," Easterbrook wrote. "We commit to raise awareness worldwide, perhaps you’ll join us in a meaningful global effort?
"And every day, let's acknowledge that between us there is simply a friendly business competition and certainly not the unequalled circumstances of the real pain and suffering of war.
"We’ll be in touch. Steve, McDonald’s CEO. P.S. A simple phone call will do next time."
Nonprofit organization Peace One Day is a key advocate of International Peace Day.
Jeremy Gilley, Peace One Day's founder, said: "This proposal from Burger King is the corporate sector at its best. Coming together, putting their differences aside and saying, ‘Come on, let’s do something to manifest a more peaceful, sustainable world.’ "