Workers at BHP's Port Hedland facilities in Australia will seek arbitration after failing to reach agreement on a new pay deal, the Combined BHP Ports Unions said on September 15, according to Reuters.

The union, representing 450 operational and maintenance workers at the site, will apply for an intractable bargaining declaration. If granted, the Fair Work Commission would have the power to set terms for the agreement.

The union and BHP have been negotiating a four-year wage agreement for more than nine months, meeting almost weekly in recent months with the assistance of the Fair Work Commission, but without resolution.

The union said in a statement that BHP was unwilling to reach an agreement reflecting the specialized skills, extreme conditions and significant personal sacrifice.

"Our focus remains on delivering a fair and reasonable agreement." a BHP spokesperson said in response to a Reuters request for comment. The company said its latest proposal was put forward a week ago and added that continued negotiations were the fastest path to an outcome.

BHP's new proposal commits to a 17% pay increase for most workers over four years, including a A$25,000 transition payment spread over two years and higher roster allowances. The union said about 40% of the workforce would be worse off under the offer.