Minera Escondida resumed copper mining operations in Chile on Sunday, August 20, and expects to be operating at about 50% of production capacity using non-unionized workers and contractors, a BHP Billiton spokeswoman told Platts Monday.

"We have started operating at Escondida on Sunday and expected to go back to around 40-60% capacity very soon. We should be running at about 50% capacity by now," the spokeswoman said.

"Talks have resumed with the workers and we have given them a new offer, but we cannot comment on the details now," she added.

Escondida, the world's largest copper mine, is said to have made a new contract offer Sunday to striking workers in a bid to end a two-week old industrial action which began on August 7 and resulted in the shutdown of the site on August 18. The mine's 2,052 unionized workers, representing 97% of the workforce, went on strike in a dispute over wages. On Friday, BHP Billiton said it had been forced to close the Escondida mine because of safety concerns over actions taken by striking workers and would pursue legal action against union workers who blocked access roads to the mine to keep out non-union workers.

AFP reported Monday that sources close to the talks said that on Sunday the company had upped its offer to 4%, plus an $18,000 signing bonus. The new offer will be shown to the union workers, who could vote on it Monday.

The miners are demanding a 13% wage increase and a $30,000 bonus, which they say reflects a tripling in global copper prices since the previous collective bargaining agreement, reached three years ago.

Escondida is majority owned by Anglo-Australian mining giant BHP Billiton. It produces 1.3 million mt/year of copper, roughly one-fifth of Chile's total production and 2.5% of Chile's entire economic output.