WASHINGTON, Dec 18 (Reuters) - Major airlines are trying to get Congress to push back the deadline for all checked baggage to be screened for explosives, a leading Democratic lawmaker said on Tuesday. The Jan. 18 deadline for baggage screening is the first major test for the Transportation Department under the newly passed aviation security law enacted in the wake of the Sept. 11 hijack airline attacks. Minnesota Rep. James Oberstar, the ranking member of the House Transportation Committee, said the industry wants to extend the benchmark by 30 days and have the date change attached to an appropriations bill still being negotiated on Capitol Hill. Oberstar accused the airlines of trying to weaken the aviation measure. "The airlines are maneuvering as they always have on airline security," he said. "There is no justification for a delay in screening checked baggage." Transportation Secretary Norman Mineta said last month his agency would not be able to meet the mark with detection equipment and other available methods, like bomb-sniffing dogs and bag searches. More recently, however, Mineta said the government would close the security gap and meet the deadline by requiring the airlines to match every bag to every passenger. The airlines, especially the biggest carriers, generally oppose "bag matching" because it would add more expense and another layer to the check-in process. It would also threaten to slow their operations at a time when airports are already besieged by long lines and inconveniences caused by new security procedures. Some airlines, security experts and others in the government and in Congress agree that a major reliance on bag matching is inadequate to protect aircraft from terror attacks. They say it could be ineffective for stopping someone who wanted to bring down a plane and commit suicide. Michael Wascom, a spokesman for the industry's chief trade group, the Air Transport Association, said he was unaware of any legislative maneuvering in Congress and would not discuss specific security steps taken by the industry. But Wascom said the airlines had every expectation of meeting industry requirements under the new law. ©2001 Reuters Limited.