Britney Spears appears to have grown bored of miming to her hits night after night, and has taken to blurting out random phrases during her Circus concerts.

The singer's latest outburst occurred during Tuesday's show in Washington D.C., when she appeared to yell "Merry Christmas!" part way through a performance of Do Somethin'.

Did Britney really deliver a festive greeting to the Washington audience...in March? Or have we mistranslated her outburst?

Check out the clip below - paying special attention around the 49 second mark - and be sure to tell us what you hear her say!

See more of Britney's Circus act below