LOS ANGELES --- The American Trucking Associations last week filed a lawsuit claiming that plans to clean up the air near the twin ports of Los Angeles and Long Beach place unfair restrictions on its association members, the Associated Press reported.

The lawsuit, filed Aug. 4 in U.S. District Court, notes that the American Trucking Associations trade group does not oppose efforts to clean up the air but is concerned that other regulations in the plans violate federal laws by unfairly regulating prices, routes and services, AP reported.

The lawsuit claims the regulations restrict the number of trucks allowed to enter the ports, thereby reducing market competition.

Truckers must agree to the plans to retain port access after Oct. 1.

"It's a barrier to entry," said Curtis Whalen of the Intermodal Motor Carriers Conference, an affiliate of the 37,000-member association. "We don't think the ports have the legal ability to do that."

The group wants the court to stop the plans from being implemented.

Defendants named in the lawsuit include the cities of Los Angeles and Long Beach along with their harbor departments and commissions.

"We feel that the program is legally defensible and we see no problem in continuing to move forward with this plan," Lee Peterson, a spokesman for the Port of Long Beach, told AP.

Both cities passed plans this year aimed at curbing truck pollution. The plans would require trucks to meet tougher 2007 federal emissions standards by Jan. 12, 2012, along with a $35 cargo fee to pay for the newer, cleaner-running trucks.

"We are committed to rolling ahead with the world's most ambitious and bold plan to simultaneously green and grow a port," Los Angeles Mayor Antonio Villaraigosa said in a statement in response to the lawsuit.

Unlike the Long Beach plan, Los Angeles would require the nearly 17,000 independent truckers who work at the port to eventually become employees of trucking companies. Critics of the plan have argued that this is a thinly veiled attempt to unionize low-wage drivers. 

In its lawsuit, the trade group claims the different restrictions placed on independent truck drivers represent "a textbook case of the need for federal pre-emption to prevent a patchwork of service-determining laws, rules and regulations."

The California Trucking Association, which has more than 3,600 members, said it supports the lawsuit.