One month after T-Mobile US announced the debut of its “BingeOn” service, which allows wireless subscribers to stream content from Netflix, Hulu and other selected online video distributors (OVDs) without charging against subscriber data allowances, YouTube accused T-Mobile of throttling, or slowing the transmission speed of, content streamed from the YouTube website, stressing that “reducing data charges can be good for users, but it doesn’t justify throttling all video services, especially without explicit user consent.”

YouTube is not included among the 24 OVDs that have met T-Mobile’s qualifications for BingeOn and that have signed onto the service. While BingeOn provides T-Mobile customers with minimum monthly data allowances of 3GB with free, unlimited streaming of content from partner websites, critics contend that T-Mobile’s policy of streaming content from these websites at lower quality in an effort to reduce network loads runs afoul of FCC net neutrality rules, which prohibit ISPs from blocking or impairing the transmission of lawful web content. Although FCC Chairman Tom Wheeler remarked last month that BingeOn was “highly innovative and highly competitive” and voiced doubt that the service contravenes the agency’s net neutrality rules, Wheeler delivered letters last week to executives of T-Mobile, Comcast and AT&T requesting further information on the video streaming practices of these companies.

Despite the fact that YouTube is not a BingeOn member, a YouTube official told reporters on Tuesday that T-Mobile is throttling the network speeds of wireless subscribers when they stream content from YouTube from other websites that  are not included in the BingeOn offering. Backing YouTube’s claims, a spokesman for the Internet Association also  charged that “T-Mobile’s new ‘streaming optimization’ program appears to involve throttling of all video traffic, across all data plans, regardless of network congestion.” Officials of T-Mobile offered no comment.