THE Vatican has been left red-faced after it emerged that a car bearing its diplomatic plates had been stopped in France with four kilograms of cocaine on board.

The car — which also contained 200 gram of cannabis — belonged to 91-year-old Argentinian cardinal Jorge Mejia, emeritus librarian at the Holy See, who retired in 2003 and who is currently bedridden.

Pope Francis, a fellow Argentinian, visited Mejia, who was confined to a hospital in Rome after a heart attack, just two days after being elected.

French radio reported that the cardinal’s private secretary entrusted the vehicle to two Italian men to take it for its annual check-up.

The two men promptly drove to Spain to buy the drugs, thinking that they would be protected by the diplomatic plates, according to RTL radio — a scenario not yet confirmed by legal sources.

The pair were picked up on Sunday at a toll station near Chambery in the French Alps on their way back.

Neither of the men has a Vatican diplomatic passport so the Vatican is not directly implicated, French legal sources say.

The Vatican confirmed that the car had been stopped in France with the drugs on board but stressed that no staff were involved in the incident.