BRASILIA (Reuters) - Brazilian state-controlled oil company Petróleo Brasileiro SA PETR4.SA owes the government billions of dollars tied to offshore exploration rights but is unlikely to pay this year, a cabinet minister said.

Brazil's Planning Minister Dyogo de Oliveira reacts during launch ceremony of the "New School" (Novo Ensino Médio) at the Presidential Palace in Brasilia, Brazil, September 22, 2016. REUTERS/Ueslei Marcelino

The government’s 2018 budget does not include any revenue from the so-called “transfer of rights” area that has sparked a dispute with the company also known as Petrobras, Planning Minister Dyogo Oliveira said in an interview on Thursday.

In 2010, Brazil exchanged offshore exploration rights for equity in Petrobras. The government argues it is now owed money due to a reassessment of the value of the assets, but Petrobras says it is owed money by the government from the reassessment.

Oliveira’s comments suggested the dispute could drag on despite the creation of a government commission comprised of representatives from several ministries this week to accelerate negotiations. There is a 60-day deadline to reach a deal.

“I don’t expect to see revenues from this process this year,” Oliveira told Reuters, though he said the government is working to reach an agreement as soon as possible.

He declined to estimate the amount the government was owed, saying only it would be billions of dollars.

The revenue could help Brazil plug a budget hole and slow down growth in public debt after it suffered a sovereign downgrade last week.

On the other hand, if a resolution is reached favoring Petrobras, the government could make payments in the form of barrels of oil, sidestepping any spending increase, Oliveira said.

President Michel Temer’s administration has struggled to push austerity measures through Congress after spending political capital to fight off corruption charges.

With Temer's approval rating in the single digits, some investors doubt he can follow through on an agenda of market-friendly reforms, such as privatizing power utility Centrais Elétricas Brasileiras SA ELET3.SA.

Oliveira said he sees little resistance from lawmakers to the plan to privatize Eletrobras through a capital increase or a related measure deregulating electricity prices, which would likely result in higher rates for consumers.

Together, the electricity reforms would produce 12 billion reais in revenues, according to the government’s budget plan.

“I don’t see Congress putting up resistance against the Eletrobras capitalization. You hear some comments about its subsidiaries or things like that, but I don’t hear comments about the main concept,” he said.

Even one-time revenue from Petrobras would not keep the government from breaking budget rules in 2019, Oliveira said, as an aging population accelerates social security payments.

Brazilian law forbids the government from issuing debt worth more than its planned investments in a given year. Breaking the so-called “golden rule” would leave Temer’s successor, who will take over after this year’s elections, vulnerable to impeachment unless authorized by Congress. Temer has said he will not run again.

Some analysts fear the government could break the rule in 2018, but Oliveira said a smaller-than-expected 2017 deficit would help meet obligations this year.

“For 2018, we are not worried. There is no risk of breaking the golden rule,” he said. “For 2019, there is no possibility of meeting the golden rule, given the size of the imbalances.”