Global credit agency Standard & Poor\'s said Tuesday that it saw little improvement in iron ore prices in the near-term and warned that smaller single-commodity miners could see their ratings slip. S&P said a slowdown in China, the world\'s largest producer and consumer of steel, and sluggishness in Europe had seen iron ore prices dive from their peak of more than US$180 per tonne to below $90 per tonne in the past two months. Prices had rebounded to between $100-110 but S&P said it \"doesn\'t expect iron ore prices to climb much further in the near term\", and warned that \"substantially debt-laden\" miners could come under pressure. \"We found that iron ore prices need to average above $120 per tonne in the near term to alleviate potential negative rating pressure for certain producers, assuming other factors such as costs and foreign exchange rates remain the same,\" S&P said in a research note. The agency said single-commodity miners such as Australia\'s Fortescue Metals Group and Ukraine\'s Ferrexpo would be under the greatest pressure, with iron ore accounting for almost all their business. Fortescue last month secured a US$4.5 billion loan to pay down debts that have seen it defer two planned expansions and cut jobs as it grapples with a commodities slowdown. Xstrata has also announced sackings and BHP Billiton, the world\'s largest miner, shelved plans to expand its massive Olympic Dam copper and uranium project in Australia after reporting a 35 percent plunge in annual profit. S&P said BHP, Anglo American and London-headquartered Vedanta were all seen as being relatively robust due to their diversified portfolios, with falls in earnings likely to be less than 20 percent were iron ore prices to remain soft. Brazil\'s Vale and Anglo-Australian Rio Tinto were more likely to suffer, with an estimated impact on earnings of between 20 and 40 percent, S&P said. Fortescue and Ferrexpo would be among the worst hit, with a fall in earnings of more than 40 percent forecast and Fortescue in particular seen as having limited flexibility to reduce spending. Australia recently slashed its mining earnings forecasts for the first time since the global financial crisis, estimating that iron ore prices will plunge 27 percent and steelmaking coal 28 percent over the next 12 months.