Every year on Bastille Day, the French ambassador to Havana hosts a grand reception in his vast Italianate home, in the Western suburbs of the city.
It is usually a popular event. Guests can count on one thing: the wine will be considerably better than that usually available in Cuba.
The Bastille Day atmosphere was very different in Havana this year
And like many diplomatic receptions here, it is a intriguing glimpse of what life was probably like for a privileged few in Havana in the 1950s.
Linen-clad staff, carefully prepared cocktails, expensively-dressed guests, that sort of thing.
But this year, the atmosphere was very different. Bastille Day became the unlikely focus of a major diplomatic fall-out between the EU and Cuba.
It all follows Cuba's recent arrest and sentencing to long prison terms of 75 political dissidents, and then its summary execution of three hijackers.
In June, the EU expressed its outrage by announcing various sanctions. High-level government visits have been ended. Cultural exchanges are being re-considered.
But the one response which seems to have really infuriated the Cuban Government involves the guest list at EU receptions.
As a small protest against the Cuban Government, all European Union embassies have pledged to invite Cuban dissidents to their national-day celebrations.
So amongst the diplomats and journalists and foreign investors sipping white wine in the French ambassador's garden, were half a dozen Cuban dissidents.
And 400 guests did not show up. All but one or two of the Cubans that were invited, decided it would be better to stay away.
Cuba's cocktail war, or canapé conflict, as it has already been dubbed, may seem trivial in the greater scheme of things. But there is a serious side to it.
There has been outrage at Cuba's treatment of its dissidents
"The Cuban Government wants us to be seen as non-people, as a complete irrelevance." said one dissident, Rene Gomez, at the Bastille day reception.
"By inviting us to events like this, European governments are proving that that is not true."
The Cuban Government accuses European governments of having double standards.
"The policy is an insult to the Cuban people," said Angel Dalmau, the Cuban minister responsible for relations with Europe.
"Would they ask dissidents to a reception in China? " he asks.
One consequence of this diplomatic spat is that EU ambassadors who invite dissidents to their homes will find themselves barred from official Cuban events.
It seems inevitable that the rift between Cuba and the EU - its largest trading partner - will widen.
Opponents of Fidel Castro have been sent a new warning
The consequences for the dissidents who attend the receptions may be far more severe.
Cuban Foreign Minister Felipe Perez Roque has threatened to use the full force of Cuban law against those Cubans who, as he puts it, act with foreign powers to subvert the government of Fidel Castro.
That same law was applied against the 75 dissidents that are now beginning long prison terms in Cuban jails.
Opponents of Fidel Castro have long known that sharing a drink with an American diplomat on this island is a very dangerous policy.
They have now been warned that a cocktail with a European, may be equally risky.