KUALA LUMPUR (REUTERS) - Petroliam Nasional Bhd (Petronas), Malaysia's state oil firm, will focus this year on increasing domestic production after posting a 45 per cent year-on-year drop in fourth quarter net profit.

That fall was a result of higher operating costs and impairment losses on property, plant and equipment, the company said on Thursday, while lower crude oil trading volume and a local currency which has strengthened versus the dollar trimmed revenue.

Unlisted Petronas finances nearly half of Malaysia's government budget and tension is growing between the firm and the state.

The company wants to link its government payments to profit rather than pay its current flat fee and to use more of its income for investment in production. For Prime Minister Najib Razak, who must call an election by April, a much smaller contribution would mean unpopular choices of higher taxes or lower spending.

Petronas' President and Chief Executive, Shamsul Azhar Abbas, said the firm would pay a dividend of 27 billion ringgit (S$12 billion) to the government in 2013, versus 28 billion ringgit last year.

"We hope production will increase from the domestic discoveries we made recently," he told reporters. "And the production from the three fields in Iraq we started will come on board by the fourth quarter."

As part of its efforts to secure more overseas reserves to stay profitable and offset falling domestic output, it recently completed a C$5.2 billion (S$7 billion) takeover of Canada's Progress Energy Resources Corp Petronas' net profit for the three months ended Dec. 31 2012 fell to 8.722 billion ringgit from 15.85 billion ringgit a year ago.

Revenue in the quarter slipped marginally, to 76.77 billion ringgit from 78.05 billion ringgit in the fourth quarter of 2011.

The ringgit traded at 3.0605 to the dollar in late December last year, versus 3.1595 at the end of December 2011.