Woodside Petroleum Ltd. (WPL.AU) said Friday it's disappointed with a planned 48 hour strike by the Maritime Union of Australia, which has the potential to negatively impact its business.

The MUA is seeking increases in allowances and wages, and plans to embark on a series of strikes at 12 shipping companies servicing the offshore oil and gas sector.

The first is set to get underway Tuesday for 48 hours at Farstad Shipping ASA (FAR.OS), which supplies offshore support vessels to drill rigs as well as producing platforms.

"Industrial action taken against Farstad or any other maritime service provider has the potential to negatively impact our business activities and damage the broader reputation of the Australian LNG industry," a spokeswoman for Woodside said.

Farstad is one of Woodside's key maritime service contractors.

"We are surprised at the scale of the outstanding enterprise bargaining claims that are being pursued by the MUA," she said.

Farstad operates 20 vessels in Australia and 17 will be impacted from the strike.

The Norway-based company overnight issued a notice to the Oslo Exchange, warning shareholders of the potential negative impact.

"Strike action will cost Farstad A$750,000 a day. This is a fraction of what our clients would lose," said Joseph Homsey, Farstad's managing director in Australia.

In addition to a 30% pay increase over three years, union members are seeking a construction allowance of around A$400 a day, up from A$89 currently.

The union wants maritime workers engaged in offshore construction to earn the same as riggers.

-By Elisabeth Behrmann, Dow Jones Newswires;

61-2-8272-4689 elisabeth.behrmann@dowjones.com