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UnitedContinental (NYSE:UAL) and U.S. Airways (NYSE:LCC) have joined Delta (NYSE:DAL) in adopting a $3 surcharge for one-way flights to Europe, a move intended to fight back against new travel regulations in Europe that require airlines pay for aircraft emissions.

The carriers confirmed on Thursday that they matched the $3 charge first implemented by Delta earlier this week following activation of the European Union law on Jan. 1 that holds carriers responsible for the amount of carbon dioxide they emit from jets.

Airlines had tried unsuccessfully to block the new law from going into affect, saying it would place too much financial pressure on companies that are already struggling to stay afloat in   today’s economic environment.

High costs for jet fuel have been one reason behind why some major U.S. airlines have had to cut capacity, increase fares and charge fees for additional services.

The law has been widely supported by environmentalists trying to stifle the amount of greenhouse gases seeping into the atmosphere; however, it is loathed by many in the travel industry, especially business travelers who frequent Europe and will have to dig deeper into their wallets to travel there.

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Some industry watchers predict airfares between the U.S. and Europe could rise by $50 to $90 as airlines try to pass along the fees to travelers, according to Reuters.

Last month, Fitch Ratings said the rule could deepen animosities between airlines and the European Union and open the door to retaliation, posing growing threats to aviation market access in both developed and emerging markets starting in 2012.

Trade organization Airlines for America, which has sued the EU saying the law violates international aviation treaties, has garnered support from China, India and other countries with international carriers.

The EU’s stance is that the cap-and-trade rule will do more good than harm, translating to just a few dollars per ticket, and encourage airlines to improve their efficiency and ultimately their profits.

In addition to UnitedContinental and Delta, American Airlines is also deeply affected by the rule, however it still remains to be seen whether that airline will join the $3 fee initiative intended to bite back at Europe as it undergoes bankruptcy proceedings.

Combined, the three major U.S. airlines get more than 20% of global revenues from trans-Atlantic flights.