Asked in an interview for public broadcaster ZDF whether taxes on the nuclear energy sector amounting to €2.3 billion per year would still be introduced, Merkel replied, "Of course."
She said she assumed the tax would be in the form of a direct levy on nuclear power plants, in exchange for an extension of the reactors' lifetimes beyond a planned shutdown in around 2020 agreed by a previous government.
"We (the cabinet) proposed a tax on nuclear power plants and as long as there is no other proposal on the table, this is the tax that will come," she said.
Some 40 business leaders lashed out at the government in a full-page newspaper advert on Saturday, warning that the proposed tax on the country's 17 nuclear power plants would hamper investment in Europe's biggest economy during a nascent recovery.
While the Environment Ministry wants some of the revenue from a nuclear energy tax to go toward promoting renewable energies such as wind or solar power, Merkel said it would go toward balancing the budget.
Merkel underlined her centre-right government's commitment to slowing the phase-out of nuclear power agreed by her predecessor Gerhard Schröder, arguing that Germany was not ready to do without the energy it supplies.
"I am firmly convinced that it is necessary to allow the nuclear power plants to run longer," she told ZDF.
Merkel's government aims to unveil a broad energy policy overhaul by the end of September, including a new plan for the nuclear phase-out.