UPDATE 1-Petrobras misses estimates on higher taxes; EBITDA slumps

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RIO DE JANEIRO/SAO PAULO, Aug 10 (Reuters) - Petróleo Brasileiro SA missed second-quarter profit estimates by a large margin after joining a tax refinancing program, putting the brakes on efforts by Brazil's state-controlled oil producer to cut the largest debt burden among major global oil firms.

Net income came in at 316 million reais ($99.54 million) last quarter, down from 4.449 billion reais in the prior three months, the company said in a Thursday statement. The result missed an average consensus estimate of 2.405 billion reais.

A decision by Chief Executive Officer Pedro Parente to join the so-called PERT tax regularization program led to a 6.234 billion-real charge, offsetting sharp cost and expense controls and falling capital spending. Narrower fuel pricing margins and waning demand weighed down quarterly results, executives said.

The results might have meant a hiccup in Parente's effort to trim debt faster to focus on output from massive reserves lying below the Atlantic Ocean's seabed. Still, he helped Petrobras regain an ability to generate cash in a sustainable manner and to tap cheaper funding, investors said.

Petrobras could resume borrowing with state development bank BNDES soon, Chief Financial Officer Ivan Monteiro said, noting that "all sources of funding, local and overseas, have opened again to us."

"While there were no large surprises, I'm pleased to see how Petrobras keeps generating cash and stay resilient despite the challenging outlook," said Pedro Albuquerque, who oversees São Paulo-based Cosmos Capital FIM hedge fund.

Earnings before interest, tax, depreciation and amortization - a gauge of operational profit known as EBITDA - fell 24 percent to 19.094 billion reais from the prior quarter. It missed a consensus estimate of 20.214 billion reais.

Debt minus cash fell 6 percent to 295.3 billion reais last quarter, the slowest reduction in the indicator this year. Still, it fell to 3.23 times annualized operational earnings in June, compared with 3.5 times in the first quarter and a 2.5 times target for year-end 2018.

"We are slowly doing the homework of fixing the company's dynamics," Parente said. ($1 = 3.1747 Brazilian reais) (Reporting by Marta Nogueira, Alexandra Alper, Rodrigo Viga Gaier, Guillermo Parra-Bernal and Roberto Samora; Editing by Sandra Maler and Andrew Hay)