The Boeing Co. notified South Carolina officials Wednesday that it will seek permits to build an aircraft assembly line for its 787 jet in North Charleston in a move that intensifies the coast-to-coast jockeying for the jobs the plant would create.

Company spokeswoman Candy Eslinger stressed that the step is merely "procedural."

"It does not mean the company has decided to locate the line in North Charleston," she said. "No decisions have been made."

She said Boeing is preparing to file for permits now out of an abundance of caution "because the permitting process is comprehensive and requires substantial lead time."

The company notified officials at the state Commerce Department, who in turn will alert regulatory agencies about the forthcoming permit requests.

"The reason we chose to notify them is so they can identify the appropriate points of contact as we gather the information required to apply for the permits," Eslinger said.

She said she did not know when the paperwork will be submitted or any details about the permits.

Boeing recently bought Vought Aircraft's local operation, which makes aft fuselage sections for the hot-selling but long-delayed 787 Dreamliner passenger jet.

The $1 billion acquisition has stirred hopes locally that the aerospace giant will build a new assembly line for the plane in the Lowcountry as the company looks to accelerate production and minimize late deliveries.

Right now, the jet is pieced together in Everett, Wash., with major components made by suppliers around the world.

Scott Fancher, the Boeing executive in charge of the 787 program, said last month that the company had initiated a study made up of a "short list" of locations for a second assembly line. It includes North Charleston, Everett and other undisclosed sites. Boeing plans to make its pick by the end of the year.

Eslinger said the company has not notified officials in Washington or any other state of plans to seek permits for the proposed 787 expansion.

"If and when that becomes necessary, we'll make those appropriate announcements as well," she said.

Wednesday's announcement could factor into an upcoming union vote in North Charleston. Several hundred local Boeing workers who are represented by the International Association of Machinists and Aerospace Workers will decide Sept. 10 whether to decertify the election that made them part of the union.

Dismantling the local union would likely make North Charleston a more attractive expansion site in Boeing's eyes, said Seattle-based aviation analyst Scott Hamilton. Relations between the company and the IAM have been strained for years in the Puget Sound area. In 2008, the union staged an eight-week strike that added to the 787 delays.

"Clearly, by having this public, it puts more pressure on your union vote and the union here and Washington's political leaders," Hamilton said of the permit disclosure.

It's unusual for a business to publicize its intent to seek permits before picking a site. On the other hand, as Hamilton pointed out, "Boeing these days can't keep a secret about anything, so they may as well be up front about it."

Boeing's local plant is on roughly 400 acres on the outskirts of Charleston International Airport. Its existing buildings occupy part the site, and the undeveloped portion could easily accommodate a new assembly plant.

At a minimum, the company would have to obtain permits from the city of North Charleston and the state Department of Health and Environmental Control.

Procedural or not, the permitting plan set off more alarm bells among Boeing boosters in Washington who have been fretting for weeks about the possibility of losing aviation jobs to largely union-free South Carolina. They issued a flurry of responses Wednesday to this latest twist in the pursuit of the new 787 line.

Everett Mayor Ray Steph- anson said Boeing's expansion needs "can be easily met in existing facilities" in his city.

"You don't need to apply for permits in Everett, there is significant capacity within the existing Everett assembly plant to accommodate additional lines including the facilities, and an experienced, skilled workforce," he said.

U.S. Sens. Patty Murray and Maria Cantwell, D-Wash., issued a joint statement saying: "There is no place in America better suited to build a second 787 line than Washington state. When it comes to infrastructure, experience, and expertise, Washington state is second to none."

Meanwhile, South Carolina decisionmakers reaffirmed their willingness to accommodate Boeing.

Gov. Mark Sanford has been involved with the recruitment efforts, said spokesman Ben Fox, who declined to discuss any incentives that the state is proposing.

"We would be excited about the potential of Boeing expanding a second line here," Fox said.

North Charleston Mayor Keith Summey was guarded in his optimism.

"They tell me it's not a done deal, and that's understandable, but I think it shows at least we've got a great chance of them coming to our area for expansion," Summey said. He said also he believes Boeing's intents are "genuine" and are not part of any labor posturing.

U.S. Rep. Henry Brown, R-S.C., has been working to cultivate an "open and communicative relationship" with the company, a spokeswoman said. Brown was one of several South Carolina officials who sent a congratulatory letter to Boeing chief executive Jim McNerney on last month's Vought acquisition in North Charleston.

Commerce Department spokeswoman Kara Borie said "it is still early in the process, but we will be working with the company to gather details." The state's main economic development agency, she said, is "committed to working with Boeing to achieve the schedule they would require for future growth opportunities."