Wellington, March 16 NZPA - Refinery margins at Marsden Pt showed "significant" improvement in the first two months of 2010, after starting to show some recovery in December, the New Zealand Refining Company says.

But releasing its throughput and margin report for January and February, the company added that, "in our opinion it would be premature to believe this signals the start of a sustained recovery in refining margins and further volatility can be expected in the coming months".

The refinery was operating at full capacity during the two-month period covered by the report, with throughput of 7 million barrels.

The average gross refinery margin (GRM) generated for the two-month period was $US6.85 ($NZ9.76) per barrel. At an average exchange rate of US71.23c, the processing fee earned for the two-month period was $47.2m.

In November and December, throughput was 7.2m barrels, with an average GRM of $US1.18 per barrel, and a processing fee earned of $8.2m at an exchange rate of US72c.