KUALA LUMPUR: Malaysian state energy firm Petronas said yesterday its second-quarter net profit shrank 30 percent to 15.22 billion ringgit ($4.89 billion) mainly due to lower crude oil prices.

Revenue at Malaysia's only Fortune 500 company sank by three percent to 70.70 billion ringgit for the quarter ending June 30, down from 72.94 billion ringgit in the same period last year.

Petronas said oil prices tanked due to the bearish market sentiment surrounding the economies of Europe, the US and China.

It added that revenue was also dampened by lower volume of oil and gas products sold due to limited opportunities, operational challenges and scheduled plant turnarounds.

Despite year-to-date numbers outpacing last year's, Petronas said it now expects current year prospects to be "lower than performance for last year".

"Slowing global economic growth and geopolitical uncertainties continue to heighten risks for the oil and gas business," it said in a report.

The first half of 2012 brought in 35.96 billion ringgit in profit and 145.87 billion ringgit in revenue compared to 34.48 billion ringgit and 138.58 billion ringgit respectively for last year.

Malaysia's largest company contributes almost half of Malaysia's budget revenues.

The oil and gas firm ended its last financial year on December 31 as part of an adjustment to align its financial year with the calendar year.