MANILA (Reuters) - Philippine Environment Secretary Regina Lopez said on Thursday she will ban open-pit mining in the country, toughening a months-long crackdown on the sector she blames for extensive environmental damage.

FILE PHOTO: A view of nickel ore stockpiles at a port in Sta Cruz Zambales in northern Philippines February 8, 2017. REUTERS/Erik De Castro/File Photo

The ban comes just days before the outspoken environmentalist-turned-regulator faces a confirmation hearing in Congress that could lead to her removal as minister after a storm of complaints from pro-mining groups.

Lopez, who has already ordered the closure of more than half the country’s operating mines and has previously described open pit mines as “madness”, said it was within her prerogative to ban the practice, which is allowed under Philippines mining law.

“Each open pit is a financial liability for government for life,” she told a media briefing. “It kills the economic potential of the place.”

The ban will take effect immediately but will not cover existing mines, she said.

Mining is a contentious issue in the largely underexplored Southeast Asian country after past examples of environmental mismanagement.

Lopez in February ordered the permanent closure of 22 of 41 operating mines in the world’s top nickel ore supplier and later canceled dozens of contracts for undeveloped mines to protect water resources.

Miners have argued her actions are illegal and no mine has yet been closed as companies pursue an appeals process that can only be settled by President Rodrigo Duterte.

The Chamber of Mines of the Philippines described her latest move as “absurd.”

“With this open-pit ban, she is essentially banning the mining of shallow ore deposits that can only be extracted using open-pit mining,” said Chamber spokesman Ronald Recidoro.

WANTS DUTERTE AS SUCCESSOR

The ban would halt the $5.9 billion Tampakan copper-gold project in South Cotabato province in Mindanao island, the nation’s biggest stalled mining venture.

Tampakan failed to take off after the province where it is located banned open-pit mining in 2010, prompting commodities giant Glencore Plc to quit the project in 2015.

Lopez has said the project would cover an area the size of 700 football fields in what otherwise would be agricultural land.

There are currently 14 open pits in the country, 10 of them abandoned, said Lopez, who flew to several mining sites in recent weeks to inspect them.

Lawmakers will resume hearings on Lopez’s appointment on May 2 after sessions in March when pro-mining groups assailed her capacity as minister.

Lopez said she was imposing the ban now because she was unsure of the outcome of the hearings.

If lawmakers reject her appointment, Lopez said she wants Duterte to succeed her.

“That’s the kind of person you really need at DENR,” she said, referring to her agency. “Brave, cannot be bought, everyone will be scared.”