But barely 24 hours later, McDonald's appear to have ended any such hopes of being able to sink our teeth into a McWhopper.
Burger King suggested the 'ceasefire' with their fast-food rivals in order to celebrate World Peace Day. If it had been agreed, the McWhopper would have been sold in a single pop-up shop half way between the two organisations' headquarters on September 21 with all proceeds going to the Peace One Day Charity.
Declining the offer, McDonald's CEO, Steve Easterbrook, responded via a Facebook post.
'We love the intention but think our brands could do something bigger to make a difference," he said.
Making the point their rivalry with Burger King is far from the 'unequal circumstances of the real pain and suffering of war,' that World Peace Day focuses on, it's pretty clear McDonald's are less than impressed by the idea.
The 'P.S A simple phone call will do next time' also suggests Ronald McDonald and co weren't keen on the public nature of Burger King's offer.
McDonald's taking the moral high ground, now that's funny.
