Industrial action will soon hit the Australian coal operations of BHP Billiton as some 4000 coking coal workers are set to walk out from their job sites beginning next week, demanding from the giant resources company better pay and solid tenure assurances.

Stephen Smyth, president of the Construction, Forestry, Mining and Energy Union's mining and energy division in Queensland, told Bloomberg on Thursday that the planned work-stoppage will hit seven mining sites of the BHP Billiton-Mitsubishi Alliance on June 14, 15 and 18.

Smyth stressed that workers belonging to the union, who last week favoured the move for a strike, believe that they deserve higher compensation and job security from a company that dominates the coking coal export industry in the country.

Analysts interviewed by Bloomberg said that the impending production halt could hurt BHP, quoting John Meyers of Fairfax IS in London as saying that "any stoppage in the current market environment is likely to be substantial."

Meyers said that the market would respond to the industrial action by pushing up the prices of coking coal and BHP would be served well to resolve the issue as hastily as possible, stressing that "it's far more costly to lose coal production than to agree to a wage increase."

Bloomberg has reported that Smyth and other union officials are currently negotiating with BHP representatives but an agreement has yet to be reached to prevent the work stoppage, which last hit the mining firm in 2001.

Experts fear that the looming strike could undermine efforts by BHP to catch up with the output shortfalls it suffered during the Queensland floods that rendered many of its sites idled by the swamping flood waters.

In an email sent by BHP spokeswoman Samantha Stevens, the company said that "BMA is extremely disappointed that the unions have elected to take this unnecessarily aggressive action.

Despite the latest move being pushed by the unions, Stevens said that BMA has decided to continue its discussions in good-faith with the workers' representatives, with the company, she stressed, offering a five percent annual pay hike and a $5000 bonus that hopefully will expedite culmination of the negotiations.