By Alex MacDonald

LONDON--India-focused Vedanta Resources PLC (VED.LN) Friday said its earnings fell by more than a third in its first fiscal quarter, compared with the same period a year earlier, largely due to plummeting oil prices and weaker prices for other commodities.

The U.K.-listed miner, India's largest natural resources company, reported a 38% drop in earnings before interest, taxes, depreciation and amortization to $645 million for the first three months of the fiscal year ending March 31, 2016. This stems from a 4% drop in revenue to $2.95 billion over the same period.

Vedanta's earnings were hit by tumbling oil prices, which caused Ebitda from its majority-owned Cairn India unit to fall 61% to $215 million during the period. Oil and gas are typically the company's biggest earnings contributor, but this quarter they were the second-biggest contributor after its Indian Zinc operations.

Vedanta is in the process of seeking shareholder approval to combine two of India's biggest resources companies--Cairn India Ltd and Vedanta Ltd.--into one operating company. However, it has faced some objections from Cairn Energy PLC (CNE.LN) in terms of valuation, according to a person familiar with the matter.

"In Q1 [first quarter] we saw continued volatility in commodity prices, but Zinc has held up quite well in view of its strong fundamentals and is now the largest contributor to our Ebitda," said Tom Albanese, Vedanta's chief executive officer.

Zinc accounted for 45% of the company's first-quarter Ebitda, rising 9% year-over-year in the fiscal first quarter to $293 million, largely as a result of a 33% increased in output from its Indian zinc operations.

Vedanta restarted iron-ore sales from the Indian state of Karnataka and said it's well positioned to re-start mining in the Indian state of Goa post monsoon season.

Write to Alex MacDonald at alex.macdonald@wsj.com

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