Brazil floated a proposal to cede control of the country’s biggest power utility, Eletrobras, in the boldest privatisation yet by a government struggling to close a record budget deficit, sending Eletrobras’ shares soaring in after-market trading.

The Mining and Energy Ministry gave Centrais Elétricas Brasileiras, the holding company known as Eletrobras, notice of the plan and said publicly that it would bring the proposal to President Michel Temer’s special council on privatisations.

While both the privatisation model and terms are yet to be decided, the government will keep a right to veto some strategic decisions, the ministry said in a statement. American depositary receipts of Eletrobras surged 20 per cent on the news, hitting $5.34 in after-market trading. Earlier, the ADRs closed at $4.45 in New York.

Temer has worked to attract private investment to Brazil’s energy and transportation infrastructure, but giving up control of a state-run company would mark a sharp contrast with other politicians’ wariness about unpopular privatisations. A successful sale of the government’s Eletrobras stake would help Temer hit a recently widened budget target and avert another debt rating downgrade after Brazil’s worst recession on record.

The government sees its stake in Eletrobras as worth at least 12 billion reais ($3.8 billion), a government source said. The value of Eletrobras’ equity stood at 31 billion reais at the end of May, according to the company’s website.