HONOLULU -- The union representing sailors on Matson Navigation Co. ships said its members may walk off the job if a new agreement is not reached Thursday night.

The International Organization of Masters, Mates and Pilots represents workers in Honolulu and along the West Coast. Union officials said members authorized a strike.

The company's contract expired on June 15 and was extended 10 days. The extension runs out Thursday at 9 p.m. Hawaii time.

The two sides scheduled a marathon negotiating session to start at 7 a.m. Thursday in Los Angeles.

Workers marched from the union hall to the downtown offices of Matson's parent company. They passed out leaflets warning passers by about their dispute.

Right now, the pay scale for masters, mates and pilots varies from $30,150, union officials said. It maintains the dispute is not about a pay raise but of parity. The union wants to end a two-tier system in place now that was designed to help Matson finance four new ships.

"They have made profit every single year, even last year with the crash of the market credit. They have not kept their word about parity and unfortunately it has come to this," said Charles Khim of the MM&P.

It claims it is not out to scare people but that the public should be aware that a strike is a possibility and they should be prepared.

"We believe it's only fair to the people of Hawaii because we are in a unique situation. After all, all our goods come in through the mainland and Hawaii would be the hardest hit if there is a shipping strike," Khim said.

Matson said it is also negotiating with two other unions that represent marine engineers and radio operators. Their contracts also expire Thursday, company officials said.

"Matson continues to negotiate in good faith with the Masters, Mates and Pilots, Marine Engineers Beneficial Association and American Radio Association regarding successor agreements. The current contract was set to expire June 15, but a 10-day extension was reached, with talks scheduled to resume on June 25," Matson said in a written statement. "Matson feels that there is still sufficient time remaining to work out an agreement. The strike vote announced today is often used as part of the negotiating process. Matson does not publicly discuss the contract issues under review with the unions."

The talks have been ongoing. The negotiations have been mostly under the radar until now.

"As a resident of this state there is a certain level of concern about bringing products in but it will be resolved," Oahu resident Lee Bender said.

Matson currently operates a fleet of nine ships they run in and out of Honolulu three times a week.

Matson's SS Mokihana pulled into Honolulu Harbor on Wednesday afternoon. It is scheduled to leave this weekend.

"There will be others, I think the next one is coming in on Friday," said Donald Marcus of MMP Pacific Ports.

A third is scheduled to arrive Sunday night. It generally takes four days for a ship to reach Honolulu from the West Coast.

Stay with KITV and KITV.com for more on this developing story.