Goldman Sachs (NYSE: GS) has maintained its base case for oil prices at $50 per barrel, saying it anticipates a return to stable long-term oil prices.

The bank said in an outlook note that confidence in long-term oil prices has increased due to improvements in technology and therefore the costs involved with shale extraction. Price fluctuations are now likely to be within the realm of 10-20 percent, rather than the quadrupling noted when new technology methods were being trialled , the note said.

"This higher level of certainty in the resource base for future supply is what helps drive our confidence," the note said.

Goldman's long-term WTI price of $50 per barrel remains slightly lower than its 5-year estimate of $54 per barrel, however, the bank said that it anticipates a positive outlook going forward – one not seen for almost 15 years.

"We believe we are going back to an environment similar to pre-2003, a period characterized by stable long-term oil prices and low oil-dollar correlation," the research note said.

The comments refer to the 1990s and early millennium, when commodity returns were generated from carry – rising prices of futures contracts – rather than direct price appreciation.

"The last time the market had this level of certainty around long-term oil prices was before the rise in long-dated oil prices in 2003, nearly 15 years ago," it said.

Goldman's comment on "low oil-dollar correlation" refers to the historical link. When the dollar has risen in value, oil prices would fallen – and vice versa.

The bank has also maintained its overweight position for the commodities sector as a whole. It is anticipating returns of five percent over the next three months and four percent over a 12 month time horizon.

"The strategic case for commodities remains solid", Goldman said, downplaying recent volatility.

The bank has upheld its near-term target for gold at $1,200/toz and its 12 month target at 1,250/toz.

Reduced oil imports from OPEC countries, growing Chinese demand for metals and positive macroeconomic data forecasts all suggest that the "base case logic remains intact," the bank said of the sector.

The comments follow a continued hunt for 'safe-haven' assets amid geopolitical uncertainty. Commodities have seen increased demand, with gold in particular trading up since the start of the year.

However, Nicholas Melhuish, head of Global Equities, Amundi, cautioned that these gains could be short-lived.

"Commodity prices look quite rich," he told CNBC Wednesday, "that's not a sector we're exposed to.

"The spot (gold) prices look relatively elevated and I think therefore there is potentially some downside to these stocks."

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