US Airways Group Inc. (NYSE: LCC), the fifth-biggest U.S. airline by traffic, has registered a slew of Internet-domain names that suggest a merger effort with AMR Corp., parent of American Airlines, is imminent.

The domains include, and

The purchase of these domain names, along with any potential transaction names, is simply a step to ensure others do not use our marks in a way that might negatively impact our brand, US Airways said in a statement, according to the Wall Street Journal.

Domain Name Wire reported the registrations on Sunday.

US Airways said in January that it was assessing a bid for AMR, which filed for bankruptcy protection in November. It hired Milstein & Co., Barclays PLC and law firm Latham & Watkins LLP to advise a potential merger.

American is the country's No. 3 airline by traffic, and a merger of US Airways and AMR would create an entity that would rival United Continental (NYSE: UAL) is size.

Delta Air Lines Inc. (NYSE: DAL), the second-biggest U.S. carrier, and private-equity firm TPH Capital are also a potential bidder for AMR.

Both US Airways and Delta beat forecasts for their fourth-quarter earnings, as higher fares and fuller planes overcame rising fuel prices. US Airways reported a net profit of 13 cents a share, beating a projected 3 cents a share. The airline saw revenue increase by 8.5 percent, while average fuel price rose 20 percent. Delta had a net profit of 45 cents per share, beating a 38-cents-a-share forecast.

The airlines are not flooded with surplus seats, Bob McAdoo, a senior research analyst at Avondale Partners, said in January.

Shares of US Airways were up 12 cents to $7.01 Tuesday afternoon. Delta was up 10 cents to $9.29.