The Obama administration will conduct a vigorous antitrust review of the proposed merger of United Airlines and Continental Airlines but will not take longer than necessary, U.S. Attorney General Eric Holder.

Holder also told concerned lawmakers at a congressional hearing that political factors will not influence antitrust enforcers examining the proposal to create the world's largest commercial airline.

"I'm confident that we will give this a good, thorough, vigorous look and make a decision on the basis of that examination," Holder told the House of Representatives Judiciary Committee.

United, a unit of UAL Corp, and Continental last week proposed the deal valued at about $3.2 billion.

Antitrust experts believe that the Justice Department will clear it since there is little overlap of common routes and no shared hubs. Antitrust enforcers, experts said, could require some divestiture to enhance competition.

United and Continental hope for regulatory clearance by the end of the year.

"We will take the time that is necessary for us to look at it, to make sure we are comfortable in the decisions that we are making," Holder said. "We will not unnecessarily delay things, but we will certainly take the time that we need to come up with a reasoned decision."

Additionally, Ohio Attorney General Richard Cordray said he is also leading an effort to examine the proposed deal.

"A merger this large may have staggering ramifications for the industry, for consumers, and for the broader economy," Cordray said in a statement. "Ohio has a lot on the line with this deal.

One of Continental's hubs is in Cleveland, where the airline has more than 30 percent of the market share, according to government statistics.

A spokeswoman for Cordray said the review is not unusual for a deal that impacts businesses in Ohio.

Texas and Ohio lawmakers in Washington have expressed concern with the merger proposal, which would put the airline's headquarters in Chicago.

Continental is based in Houston.
Holder's response was prompted by a question from Representative Sheila Jackson Lee of Texas concerned about plans to establish the new carrier's headquarters in Chicago, where United is based.

"I can assure you that political considerations will not be a part of that process," Holder said.

Separately, the Federal Aviation Administration (FAA) on Thursday proposed a $325,000 fine against Continental for allegedly operating a Boeing 737 on at least a dozen flights without properly maintaining the landing gear.

Continental has 30 days to appeal the civil penalty, which regulators say arose from the airline's failure to properly update its maintenance logs and promptly fix the landing gear problem.

Continental said it was reviewing the FAA's concerns about aircraft logs, and questioned the agency's view of how the airline initially handled the matter on a flight from Houston to Los Angeles in December 2008.

The FAA said a warning light indicated a problem with the right main landing gear after takeoff but the flight was permitted to continue. It eventually was diverted to Phoenix after the crew noticed extra fuel burn, the FAA.

Continental said the plane was diverted because of headwinds, not maintenance. (Reuters)