By Georgi Kantchev 

Oil prices posted gains on Friday, but analysts cautioned that a sustained recovery is unlikely until there are more signs of production cuts in the oversupplied global market.

Futures have been moving largely sideways in recent weeks, oscillating between gains and losses, which some market watchers have interpreted as the oil price finally bottoming out after its precipitous fall. Oil has shed close to 60% of its value since midsummer on a toxic combination of ample global supplies, lackluster demand for the commodity, and a strong dollar.

On the New York Mercantile Exchange, March-dated WTI futures, the U.S. price benchmark, flirted with $45 a barrel, up about 1% from Thursday's settlement. Brent crude, the international marker, was up 0.7% at $49.50 a barrel on London's ICE Futures exchange.

"The fall in oil prices will have an effect on supply and there are signs that production will be cut in the future," said Thina M. Saltvedt, senior oil analyst at Nordea Bank Norge. "But until we see those cuts, it is too early for a serious rebound. There is still a lot of oil floating around."

Oil majors have announced spending cuts in recent weeks to cope with the price rout. Royal Dutch Shell said Thursday it would curb its planned spending over the next three years by some $15 billion and scale back investments in shale. ConocoPhillips also said it would slash its capital budget as the company reported losses in the fourth quarter of last year.

"Shell was the first of the major oil companies to report yesterday and, if its results are representative of what is going on in the industry as a whole, the outlook isn't pretty," Bill McNamara, an analyst at Charles Stanley, said in a report.

Even if oil prices have steadied for now and are projected to rise later in the year as global supply reacts to the lower price environment, analysts are skeptical about the strength of any rebound.

Russ Koesterich, managing director and chief investment strategist at BlackRock, said in a report that "oil prices are likely to stabilize and rise over the long term, but this won't be immediate. Nor is the rise likely to take prices back to the upper end of the previous range."

Meanwhile, Saudi Arabian King Salman bin Abdulaziz has ordered major changes to his government, including a cabinet shuffle, but decided to keep veteran oil minister Ali al-Naimi in place.

Mr. Naimi, long one of the most influential oil-price brokers in the global market, was the main strategist behind the November decision by the Organization of the Petroleum Exporting Countries to keep its oil output steady in a bid to protect the cartel's market share against booming U.S. shale production.

Investec, the international banking and asset management group, thinks that OPEC is now committed to a "war of attrition," playing a dangerous game in which it either blinks, or digs in for the long haul.

"We suspect the latter, despite the inevitable pressures on the budgets of individual OPEC members," the group said. This would make for a slow and painful recovery, instead of the V-shaped bounce in prices many in the oil industry had been hoping for, it added.

The price slump, however, is good news for the global economy, reducing gas prices at the pump and providing a boost to economic growth for net importers of oil.

Barclays estimates that the halving in crude prices in the past six months, if sustained for the whole of 2015, would mean a transfer of $1.6 trillion from oil-producing to oil-consuming countries.

Nymex reformulated gasoline blendstock for February--the benchmark gasoline contract--rose 0.3% to $1.3574 a gallon, while ICE gas oil for February changed hands at $479 a metric ton, up $5.50 from Thursday's settlement.

Eric Yep in Singapore contributed to this article.

Write to Georgi Kantchev at georgi.kantchev@wsj.com

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