In a feud over retransmission fees that could hit sports fans where they live, Fox Networks Group says it could remove its channels from Charter Spectrum cable systems — including the former Time Warner Cable system in the Milwaukee area.

Fox Networks says its channels on Charter Spectrum, including FX, the National Geographic channels, Fox Sports and the regional Fox Sports outlets, including Fox Sports Wisconsin, could do dark unless the companies can reach an agreement. A website created by Fox says it could happen Monday, April 10; some media industry sites, including Deadline Hollywood Daily, predicted Friday that it could happen as early as Saturday.

The spat does not include broadcasting stations carrying Fox, Fox News Channel or Fox Business Network.

An agreement on fees between the two sides expired on March 31, but had been extended so negotiations could continue.

Now, both sides have gone to their versions of the mattresses: Charter, issuing statements via press release, and Fox creating a website, KeepMyNets.com, urging subscribers to tell the cable company they want their programming. Fox also posted a video on the site and on YouTube showing viewers what they could be missing, including the new season of “Fargo” on FX and, in some markets, the NBA and NHL playoffs. In Milwaukee, Fox Sports Wisconsin is the primary TV outlet for Brewers baseball games.

“Fox and Charter have an agreement to carry the Fox networks that Charter has chosen to ignore,” Fox says on KeepMyNets.com. “We’re disappointed that despite our best efforts to reach a resolution, Charter Spectrum subscribers could lose access to multiple Fox sports and entertainment networks on April 10.”

In a just-as-blunt statement, Charter countered: “Fox is trying to gouge our customers using the increasingly common tactic of threats and removal of programming. They are attempting to extort Charter for hundreds of millions of dollars. We will continue to work towards a fair agreement.”

Battles over retransmission fees are becoming an increasingly common part of the TV viewing landscape.

Hearst Television stations have been off the Dish Network satellite service since March 3 in a dispute over fees. And earlier this year, Univision pulled its channels off Charter Spectrum systems after suing the cable company over its decision to Univision the fees negotiated by Time Warner companywide vs. the higher fees it had been paying under its existing contracts with Charter. Univision programming came back to charter as the result of a court order soon after.