Apple chief executive Tim Cook has said the firm takes the working conditions of staff that produce its products "very seriously" and fires partners that break its guidelines.
Cook's comments came at the Goldman Sachs investor conference, a transcript of which was put online by macrumors, and come in the same week the firm announced it has commissioned an audit of its Foxconn factories by the Fair Labor Association (FLA).
"Whether workers are in Europe or Asia or the United States, we care about every worker. We are very connected to the process and we understand working conditions at a very granular level," he said.
"Our commitment is simple: every worker has the right to a fair and safe work environment, free of discrimination, where they can earn competitive wages and they can voice their concerns freely. Apple's suppliers must live up to this to do business with Apple."
He said the firm was working hard to ensure no children were employed in the production of its devices and that strong action was taken against those found to use underage labour.
"We think the use of underaged labour is abhorrent. It's extremely rare in our supply chain, but our top priority is to eliminate it totally. We've done that with our final assembly and we're now working with vendors farther down in the supply chain," he said.
"If we find a supplier that intentionally hires underage labour, it's a firing offense."
Cook also said he thought the huge growth of the firm's iPad devices was evidence that tablets would replace the majority of PC sales in the future.
"From the first day [the iPad] shipped, we thought that the tablet market would become larger than the PC market and it was just a matter of the time it took for that to occur. I feel that stronger today than I did then," he added.
"That doesn't mean the PC is going to die. But I believe the tablet market can replace the unit sales of the PC market, and it's just a matter of the speed at which that happens."
To date Apple has sold some 55 million iPads, helping to drive the success of the firm even higher, with its share price to pass the $500 mark for the first time in its history on Monday.
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