News Katy Perry Accepts Britney Spears Impression Challenge By Rosalyn Oshmyansky 12:54 PM PDT, August 24, 2014 Getty Images It all started when Britney Spears did a spot-on Woody Woodpecker impression on Instagram. Now, she's throwing down the gauntlet to fellow songstress Katy Perry.After Katy complimented Britney's video, Britney challenged Katy on Twitter, writing, PICS: 9 Nearly Nude VMA Looks Including Britney's To this, Katy responded that she is accepting the challenge, upping the ante by promising to reveal her best impression on the MTV VMAs red carpet.@britneyspears I'll show u my best impression on the red carpet at the VMA's tomorrow... Wait for it bb.— KATY PERRY (@katyperry) August 24, 2014 NEWS: Hear Britney Spears with No Auto-TuneIt's anyone's guess who Katy will mimic -- maybe Britney herself? And one has to wonder -- will this become the next Ice Bucket Challenge?The MTV VMAs red carpet starts at 7 p.m. ET/PT.Find out who is most likely to offend at this year's VMAs.