In a move to protect its cruise ship industry, the Port of Quebec is seeking a temporary injunction against environmental groups opposed to a controversial liquid natural gas project slotted for the St. Lawrence River.

Lawyers representing the Port of Quebec appeared in court Tuesday afternoon to request a temporary injunction against opponents of the Rabaska liquid gas plant, alleging the protesters are jeopardizing the waterfront's lucrative cruise industry.

They're asking the court to bar any opponent of the project from speaking about the impact of the liquid gas terminal project on the cruise ship industry, without prior permission from port authorities.

Citizen and environmental groups have long opposed Rabaska's proposal to build an $800-million liquid gas terminal in the heart of the St. Lawrence. But the injunction itself was spurred by a letter sent to a cruise ship company from an Île d'Orléans resident.

Patrick Plante wrote a letter to a subsidiary of cruise ship company Carnival, expressing concerns about the impact of the natural gas plant on cruise boats touring the port.

"I just wanted to know if the cruise companies were contacted about the project and whether they were worried," Plante told reporters Tuesday afternoon.

Plante had no right to meddle, and it could damage the multimillion-dollar cruise industry that benefits Quebec City, said port authorities.

"[It will] have a negative impact on the 15 years of work we're doing to develop the international cruise business in the St. Lawrence," said Martine Bélanger, a port spokeswoman.

Opponents argue the injunction is too drastic and impinges on their right to free expression. "They're using a bazooka to get rid of a mosquito," said André Bélisle, president of the Association Québécoise de lutte contre la pollution atmosphérique, an environment group.

Bélisle said people are concerned about the injunction because it may limit their ability to speak out at a series of public consultations on the Rabaska project, scheduled to start in December 2006.

The Quebec court has not said when it will rule on the injunction.