The maritime union represents hundreds of workers on vessels that serve the oil and gas, and mining industries.
BHP Billiton said a possible industrial action by MUA members at Port Hedland would have "severe consequences for Australian exports and would damage the country's international reputation, and its national interest".
Meanwhile, the petroleum and resources industry association AMMA said the maritime union is using "deceptive" tactics to justify taking strike action against a pool of offshore workboat companies that have been trying to negotiate new work agreements for more than a year.
AMMA
