Update, June 5: Now Verizon has gone from posting online rebuttals to cease and desist orders.

According to a letter obtained by CNBC, the broadband provider has demanded Netflix stop presenting its viewers with messages blaming Verizon and other internet service providers for poor streaming performance.

The letter was sent from Verizon's attorney Randal Milch to Netflix's General Counsel David Hyman.

"There is no basis for Netflix to assert that issues with respect to playback of any particular video session are attributable solely to the Verizon network," Milch wrote in the cease and desist letter.

In the same order, Verizon demanded Netflix present any evidence and documentation that proves it is at fault for slow network speed within the next five days.

In response, Jonathan Friedland, a Netflix spokesperson, told CNBC, "This is about consumers not getting what they paid for from their broadband provider."

"We are trying to provide more transparency, just like we do with the ISP Speed Index, and Verizon is trying to shut down that discussion," he said.

Original story below…

Netflix isn't shy about calling out internet service providers for their subpar speeds, and now the video streaming giant is posting bulletins to users directly blaming said providers.

Vox Media Designer Yuri Victor was one of the first users to see a new message when he tried to watch Netflix on his MacBook June 3.

It seems the video tripped over some clogged bandwidth and Netflix prompted Victor with a message putting the blame on Verizon for slow speed as it rebuilt the buffer.

"The Verizon network is crowded right now," the message read. "Adjusting video for smoother playback…"

Verizon isn't laying down

Over on Twitter, Netflix spokesman Jonathan Friedland explained the message serves to advise users when their network is congested and isn't specific to Verizon customers. Rather, users can expect the message whenever their video cuts out, no matter who their broadband provider.

Verizon isn't taking this one sitting back, though. The telecom fired back in a blog post, calling the message a "PR stunt"

"This claim is not only inaccurate, it is deliberately misleading," Verizon wrote. "It is sad that Netflix is willing to deliberately mislead its customers so they can be used as pawns in business negotiations and regulatory proceedings."

Verizon continued that the issue is actually Netflix's fault and its message should read, "the path that we have chosen to reach Verizon's network is crowded right now."

The blame game

This isn't the first time Netflix has fired shots against ISPs over slow speeds. Every month the House of Cards house publishes the ISP Speed Index, which evaluates the streaming speeds of all internet providers.

Netflix has been increasingly fed up with the slow streams ISPs provide. Despite signing deals with Comcast for 65% faster speeds - and a similar deal with Verizon - it still railed against the cable company and its upcoming merger with Time Warner Cable.

This time it seems Netflix is sending an even more direct response to Verizon and ISPs in general, perhaps to coax users over to its side by blaming providers for buffering problems.

Meanwhile, internet companies could have their own agenda, claiming Netflix accounts for 30% of peak residential internet traffic. ISPs seem keen to have Netflix pay up for hogging their networks.

Expect to see even more quibbles between Netflix and the ISPs it depends on as the net neutrality fight wages on.