Hillary Clinton has taken the special relationship to a new level with a gushing appraisal of David Miliband, who the US secretary of state described as "vibrant, vital, attractive and smart".

The extravagant compliments were delivered in an interview with Vogue magazine, which put journalistic objectivity to one side to describe Britain's foreign secretary as "tall and dashing". The interviewer added for good measure: "I got a crush over the phone in about five seconds partly because of his accent."

But he was outdone by Clinton, who responded: "Well, if you saw him it would be a big crush. I mean, he is so vibrant, vital, attractive, smart. He's really a good guy. And he's so young!"

Vogue describes Miliband as smitten too, but in a more buttoned-up way: "She applies intellect but also psychology to the dossiers that she's studying," he said of Clinton. "She's delightful to deal with one on one. She's someone who laughs and can tease, and she's got perspective as well."

Miliband and Clinton are not the first he-she pair of transatlantic diplomats to hit it off. Condoleezza Rice took Jack Straw to an American football game, and while neither was as forthcoming as Clinton, Rice's actions spoke louder than words when she gave up her bed on an overnight flight to Baghdad and slept on the floor of the plane.