Two fast food chains are considering collaborating on the ultimate burger.

Rival fast food chains to collaborate?

Rival fast food chains to collaborate?

Burger King has asked McDonalds to help them create the McWhopper, a burger based on their Big Whopper and Big Mac sandwiches, which could be served in Atlanta, Georgia for World Peace Day, the Daily Mirror newspaper reports.

Fernando Machado, senior vice president for global brand management at Burger King, said: ''Our proposal is designed to generate the most attention and awareness possible for Peace Day and the work of the non-profit organisation 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.''

If it goes ahead, the burger will be offered free to customers at the pop-up shop that declare who they will make peace with.