The search engine, which , made the comment in a highly confidential document, which was obtained by Viacom and presented in the company's lawsuit against Google.
Viacom sued Google in 2007 for $1bn in damages for hosting infringing content on .
The comments came to light after the latest batch of documents used in the case, which is expected to go to trial later this year, were unsealed.
According to the , in other unsealed case documents Google labelled YouTube as a "rogue enabler of content theft".
The search engine also proposed it distance itself from the video-sharing site "based on our respect for copyright" and that a "play first, deal later" policy should be adopted when dealing with "hot content".
"It's revealing that Viacom is trying to litigate this case in the press," YouTube said.
"These documents aren't new. They are taken out of context and have nothing to do with this lawsuit."
The move comes just a month after YouTube claimed Viacom had been "continuously and secretly" for years.