(Reuters) - Global miner BHP Billiton (>> BHP Billiton Limited) (>> BHP Billiton Plc) reported a 4 percent drop in quarterly iron ore output following a fire at its Mount Whaleback mine in Australia in June, but said it still expects to hit its annual production target.

Production was 64 million tonnes in the fiscal 2018 first quarter versus 67 million tonnes a year ago, the company said.

The figures take into account iron ore produced for the company and its joint venture partners at its mines. BHP's share for the quarter was 55.6 million tonnes.

UBS had forecast a figure of about 63.6 million tonnes.

BHP on June 1 temporarily halted operations at its Whaleback mine, the largest of seven operated by the company in Australia, due to a fire.

The miner maintained fiscal 2018 guidance of 275-280 million tonnes of iron ore.

Uncertainty over China’s demand for imported ore as its steel industry undergoes structural change and speculative trading in contracts has led to a roller-coaster ride for prices this year, trading widely between $53 and $95 a tonne.   

Iron ore currently sells for around $63 a tonne <.IO62-CNO=MB>.

Petroleum production for the quarter slipped by 8 percent to 50 million barrels of oil equivalent in what was BHP's weakest quarterly petroleum output since 2011.

BHP's board is under pressure from activist shareholders led by New York-based Elliott Management to divest U.S. shale holdings and narrow its focus to hard-rock mining.

BHP said divestment of a small portion of the onshore Hawkville acreage was completed in the September 2017 quarter, with "work underway" to exit the remaining acreage.

Elliott was not immediately available to comment.

BHP’s quarterly copper output rose 14 percent to 404,000 tonnes, with fiscal 2018 guidance maintained at 1.655-1.790 million tonnes.

(Reporting By Shashwat Pradhan in Bengaluru; Editing by James Regan and Jonathan Oatis)

Stocks treated in this article : BHP Billiton Plc, BHP Billiton Limited