Commercial vehicles are no longer allowed to cross the Frank J. Wood bridge, the Brunswick Police Department announced Monday.

The Frank J. Wood Bridge carries traffic on Route 201 between Topsham and Brunswick.

The new rules apply to buses and commercial vehicles with a gross weight of 26,001 pounds or more. Essentially, any vehicles that require a Class B license to operate are not allowed over the bridge, Brunswick Police Chief Scott Stewart said.

The new rules went into effect Monday, although enforcement will not begin until Tuesday, Stewart said. The decision was made by Maine Department of Transportation.

Drivers who do not comply with the rules will be subject to a $325 fine. Stewart said the department is seeking voluntary compliance and that police handed out flyers on Monday to inform area businesses about the new rules.

The bridge, built in 1932, is at the center of a lengthy legal battle as a local group fights for its preservation while the state is pushing to replace the span. An appeal process through the First Circuit Court of Appeals in Boston is underway and both parties are awaiting a decision. Maine DOT maintains that building a new bridge would be more cost-effective than upgrading the structure.

According to Maine DOT spokesman Paul Merrill, the restrictions announced Monday were put into place because of “non-compliance” with the previous restrictions. Merrill said more information will be available on Tuesday.

Last month, Maine DOT changed the weight limits on the bridge to 10 tons, or 20,000 pounds, due to public safety concerns following a state inspection in September. The inspection showed “severe section loss on the 90-year-old bridge,” a statement read at the time.

Prior to the October announcement, the current maximum was 25 tons.

“I want to express my continued frustration that there is no legal means for the Council to take any action to speed up what is happening with the case pending before a federal court,” Town Councilor Dan Ankeles wrote on a social media post. “Like all of you who depend on this bridge, we are forced to wait until a decision has been rendered. However you may feel about how we got here or what the solution should be, I think we can agree that the current situation is not acceptable and that people should be able to count on a safe and reliable crossing through the heart of Brunswick and Topsham.”