Petronas' chief executive has reiterated that improved oil prices have led to a steady rise in upstream oil and gas activity, but there are concerns that costs are showing signs of increasing.

Speaking at the OTC Asia event, Zulkiflee Wan Ariffin said the rise in activity was evidenced by the number of active drilling rigs "which will trigger more opportuinities for the industry".

"In Malaysia, for instance, we successfully achieved first production in 11 projects last year. However, as the outlook remains uncertain it is imperative for us to continue to be vigilant in maintaining cost discipline and driving efficiencies."

He added that with the oil price recovering, there was a concern that costs were showing signs of increasing "at a worrying rate which is being driven by a premature exuberance by industry players".

"If we do not keep this in check, the industry runs the risk of negating the value we have gained from intensive cost efficiency measure in the past three years."

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