JOHANNESBURG (Reuters) - Anglo American Platinum <AMSJ.J> said on Friday it had offered to start wage talks ahead of the expiry of current agreements next year in a bid to get more than 30,000 wildcat strikers back on the job at several of its mines in South Africa.

"If the offer is accepted, the understanding is that employees would return to work on Monday, 12 November, after which date the offer will lapse," the world's top platinum producer said in a statement.

The company, commonly known as Amplats, said any agreement reached would not be implemented before July 1, 2013, when current wage deals expire.

The cost of the wildcat action is mounting and Amplats said it had lost almost 168,000 ounces in platinum production, worth over $250 million at current spot prices.

Amplats also said it had offered a one-off allowance of 4,500 rand ($520) to employees. But it said it simply could not afford the demands being made.

"The workers' current demand of a salary increase of 4500 rand per month would cost approximately 2.6 billion rand, an amount that is clearly not affordable in a year when the company is experiencing such economic challenges," chief executive Chris Griffith said.

South Africa's gold and platinum sectors have been shaken by months of illegal and often violent strikes which have resulted in the deaths of around 50 people so far this year.

Most of the affected gold operations are back to work but Amplats, a unit of global mining giant Anglo American <AAL.L>, is still struggling with crippling strikes at a time when the viability of its operations are being scrutinized. ($1 = 8.7373 South African rand) (Reporting by Ed Stoddard; Editing by Ed Cropley)