BHP Billiton’s shares have opened higher after it maintained full year production guidance for key commodities in its latest quarterly report.

The world’s largest diversified resources company posted production and sales figures for the March quarter that were slightly below expectations due to cyclone-related weather.

However it has posted record iron ore production for the nine month period to March and said it was on track to produce a 183 million tonnes in Western Australian for the year.

BHP shares were 25 cents, or 0.78 per cent, higher at $32.40 at 1035 AEST.

The world’s third-largest iron ore producer, after Vale and Rio Tinto, shipped 44.4 million tonnes and produced 44.2 million tonnes during a quarter when iron ore prices were high, averaging above $US140 a tonne.

Production was five per cent lower than the previous quarter but three per cent higher for the same period last year.

Production guidance for the company’s second-biggest earnings division after iron ore, petroleum, for about 240 million barrels of oil equivalent was also unchanged.

Production in the March quarter of 55.42 million barrels was below some expectations.

It was two per cent below the same period last year and seven per cent down on the previous quarter, reflecting less drilling in the US and less demand in southern Australia where its Bass Strait operations are.

However it said its onshore shale operations in the US produced more than five million barrels of liquids during the quarter and Eagle Ford was now its single largest liquids producing field.

The expensive and controversial $20 billion-plus US shale acquisitions were hit by writedowns last year as gas prices fell, but have since risen.