The battle between air carriers and leading travel portals is intensifying.

Expedia (Nasdaq: EXPE) and American Airlines parent AMR (NYSE: AMR) broke ties over the weekend, meaning that the popular travel website will no longer offer American and American Eagle flights through its website.

AMR broke free from Orbitz Worldwide (NYSE: OWW) two weeks ago, claiming it hasn't missed a beat since pulling its flights and schedules from Orbitz.com. It may seem that way now, but it's hard to believe that AMR will continue to fill its planes if it continues to engage in fisticuffs with travel portals over fees.

This is just a huge step backward for the industry. Nobody wins if travel-booking websites have fewer options for its visitors. It may lead to travelers paying more for their flights, but that's not entirely a major coup for the carriers that continue to offer their fares through pared-back sites. Consumers will grow to distrust the sites, leading them to go through several sites to make sure they have the best deal. Savvy surfers may do that already, but it ultimately creates confusion for mainstream visitors.

In short, portals will suffer from lower conversion rates, carriers will have greater uncertainty, and the Internet just got a tad more cumbersome for passengers.

This may help "name your price" juggernaut priceline.com (Nasdaq: PCLN) or deals publisher Travelzoo (Nasdaq: TZOO) as carriers discount unfilled capacity in the chaos. This may also be a growth catalyst for aggregators Kayak.com and Microsoft's (Nasdaq: MSFT) Bing Travel, but even they may provide incomplete spectra of travel options.

The Internet's allure is the free flow of information. Right now, the online travel industry isn't letting that happen.

Who do you think is right in this battle? Share your thoughts in the comment box below.

Microsoft is a Motley Fool Inside Value pick. priceline.com is a Motley Fool Stock Advisor recommendation. Motley Fool Options has recommended a diagonal call position on Microsoft. The Fool owns shares of Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.

Longtime Fool contributor Rick Munarriz has been leaning on travel websites since the 1990s. He does not own shares in any of the companies mentioned in this story. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.