Google acknowledged late Monday that it is considering a subscription service that would allow viewers to skip the ads that run before many YouTube videos.

That move would dramatically change the revenue model for the video colossus. Most of YouTube's services are free, so the site largely relies on advertising to pay the bills.

"YouTube right now is ad-supported, which is great because it has enabled us to scale to a billion users; but there's going to be a point where people don't want to see the ads," YouTube CEO Susan Wojcicki said at a conference sponsored by the website ReCode, which posted about her comments.

She called a subscription arrangement "an interesting model" and added that YouTube is "thinking about how to give users options," according to ReCode.