The FTSE 100-listed company has been reviewing high-cost office locations including London since last year, as it battles falling commodity prices.
An internal announcement said the company is aiming to reduce the number of London-based jobs to 262 from 479. It also wants cut the number of Johannesburg employees to 206 from 244, after reviews of its African operations meant it needed fewer administrative posts in South Africa.
“As you are aware, one of our priorities for 2013 is to significantly reduce costs across the business,” Rio Tinto said in an emailed memo to employees.
“Given the increasing volatility of our operating environment and challenging economic conditions, this is more necessary than ever.”
Rio last year cut office staff in Australia, where much of the group is managed, targeting Melbourne and closing its Sydney office.
“Like others in the industry, Rio Tinto is facing the challenge of increasing costs and is taking action to tackle this,” a Rio spokesman said.
“As a result there will be a reduction in the number of roles in London, so the company has begun a consultation process with staff.”
Rio said this month that its cost-saving push for 2013 was on target thanks to job cuts and improved productivity.
Earlier this month, Rio Tinto’s chief executive Sam Walsh said that operations had achieved a “solid performance” in the first quarter, despite a drop in copper production.
Walsh, who replaced Tom Albanese earlier this year, said that cost-cutting measures had been put in place. “We are making good progress in achieving our cost reduction targets and other priorities for 2013, and are determined in our pursuit of greater value for shareholders,” he said.