Halliburton Co (HAL.N) warned of headwinds in its international operations and pricing pressure for its oilfield services in North America, its largest market, as an extended slump in oil prices continues to force drillers to slash spending.

The company's shares rose 3.8 percent to $48.69 before the bell on Monday after it posted a better-than-expected quarterly profit, helped by higher revenue and operating income from Latin America, the Middle East and Asia.

However, revenue and profit from all other regions fell due to the global slump in oil prices LCOc1 CLc1, which have nearly halved since peaking last June.

"Industry prospects will continue to be challenged in the coming quarters," Chief Executive Dave Lesar said in a statement.

Halliburton agreed to buy smaller rival Baker Hughes Inc (BHI.N) for $35 billion last November, to better negotiate the slump in oil and resist pressure from oil producers to slash prices.

Excluding one-time items, Halliburton earned 49 cents per share, above the average analyst estimate of 37 cents, according to Thomson Reuters I/B/E/S.

Analysts covering the stock have cut their first-quarter earnings estimate for Halliburton by over a third in the past month.

Revenue fell 4 percent to $7.05 billion, but beat the analysts' average expectation of $6.96 billion.

Halliburton's shares closed at $46.89 on the New York Stock Exchange on Friday. The stock has fallen nearly a third since June.