Less than two months into his tenure as Rio Tinto’s CEO, Sam Walsh is under pressure from debt reaching $33 billion, leading ratings agency Standard & Poor’s to downgrade its credit rating outlook on one of the world’s biggest miners to negative from stable.

The S&P announcement puts Walsh, who succeeded Tom Albanese last month, under pressure to slash operating expenses and reduced capital costs in the face of a potential collapse in iron ore prices; this means Rio could lose its valued single-A credit rating in a little as a year’s time.

S&P analysts added that, while $150/metric ton (mt) iron ore prices are high, they only spell temporary good news. Moreover, in 2012, company debt surged to $26.7 billion from 2011’s $21.5 billion, owing to capital costs that hit a record $17 billion. With lower commodity prices, iron ore exports to China are now $ 151/mt; Rio also hopes to sell a Pacific aluminum division.

S&P also added that Rio, despite $13 billion in announced cuts, would be compromised by a “progressive” dividend policy barring large disposals, or if iron ore prices remained over $120/mt, agency analysts said.