Some of my best friends are one-legged Lithuanian dancers

Friends close to Westmonster (ahem) at college used to refer to a tasteless joke that fell flat as a "floater" - it would linger in the pan for days after it had been issued, refusing to go away, and would remain there to wink at you malevolently every time you tried to forget it.

Poor ol' Cameron seems to be having the same problem with his "gag" about one legged Lithuanian dancers. P'rhaps you just had to be there, but Hopi Sen is not impressed.

Neither, it may be said, is the Lithuanian Ambassador.