The trouble, it seems, is the location. The Titanic sits above Oliver Peyton's Atlantic Bar and Grill, in what used to be the Regent Palace hotel, off Piccadilly Circus in the West End of London.
The two restaurants' quarters are a little too snug for comfort. The Atlantic's management is getting increasingly irritated by confused customers thinking the two are connected. "We've got nothing to do with them," said a spokesman.
It is a food fight made in heaven: a clash of London's top restaurateurs under one roof. Both favour an exclusive guest list - White's restaurant will be open to all comers but the bar will be members only, while the Atlantic's door is still jealously guarded by bouncers.
Peyton's team may feel understandably galled when they hear that a section of London's most fashionable population is in the building, eating and drinking at another venue.
A fortnight ago, Peyton, who also owns London's painfully trendy restaurants Mash and Coast, told the Evening Standard's Londoner's Diary, "I am not happy with what Marco Pierre White has done."
Yesterday a spokeswoman confirmed that Peyton had served a High Court writ on his landlords, the Granada group and Post House Hotels. Peyton argues that an exclusion clause in his lease prevents the landlords from letting the property to another restaurant.
Sarah Canet, Peyton's spokeswoman, says, "We want to reiterate the fact that our dispute is not with Marco Pierre White. It's not a feud. The dispute is between us, Granada and Post House Hotels; it's about the lease and a term within it. It's not just to do with them bringing in Marco but about other things they're doing."
Although both sides deny any personal fracas, the division of the two camps seems particularly marked, given their choice of PR representatives: each has hired one half of former husband-and-wife team Alan and Elizabeth Crompton-Batt, who are now divorced.
Yet as the Mayday martinis were being lined up last night, both sides refused to be drawn.
Alan Crompton-Batt, acting for Marco Pierre White, said: "We haven't done anything wrong except for parking our tanks on Oliver's lawns. At least we respect the quality of what he does. And, yes, Marco and Oliver could easily sit down and have a beer together." Precisely in whose restaurant he wouldn't say.