Christian Schmidt’s action has been met with outrage after ordering officials to vote in favour of renewing the controversial weedkiller – against advice from her Chancellor.
Angela Merkel said: “As for the vote of the agriculture ministry yesterday on glyphosate, this did not comply with the instructions worked out by the federal government.”
Mr Schmidt’s decision also angered Social Democrat (SDP) politicians, especially from Environment Minister Barbara Hendricks, who opposed the renewal.
The German U-turn reportedly swung yesterday’s vote and a ban on the chemical was postponed.
Ms Hendricks said that Mr Schmidt had acknowledged her objection in a text message ahead of the vote, and so should have abstained.
He told public broadcaster ARD: “I have made the decision on my own and within the responsibility of my department,” adding that he made the decision in an “objectively oriented matter.”
The Greens were also angered who called for him to resign.
Green MP Renate Künast told the news agency DPA it was “unbelievable” that Schmidt approved a five-year renewal of the license for the weedkiller despite a lack of agreement within the government.
If Schmidt had acted without Merkel’s knowledge, she said, he should be sacked.
The row between the SPD and Mrs Merkel’s Christian Democrats (CDU), along with their Bavarian sister party, the Christian Social Union (CSU) could destabilise an already precarious situation even before the two camps embark on talks on renewing their alliance after previous talks, which did not involve the SPD collapsed.
Merkel turned to the SPD after she failed to form a three-way coalition with the pro-business Free Democrats (FDP) and the ecologist Greens, which created a political impasse unseen in the post-World War Two era.
Should these new talks with the SPD ultimately prove to be fruitless this would leave Mrs Merkel in a virtually untenable position as she would be unable to form a majority government and forcing her to consider her position or be forced to call fresh elections.
EU commissioners banned the weedkiller earlier this month over fears it caused cancer but farmers reacted angrily to the news.
Glyphosate has been a key component in weedkillers for more than four decades but the European Commission decided not to extend the product’s licence beyond the next five years.
There is currently no other viable alternative with experts predicting far-reaching consequences if the substance is removed from sale.
Copa Cogeca, the organisation representing European farmers, called the decision “absolutely unacceptable”.
Not only is it used by farmers but also gardeners and can be used to eradicate the growing menace o Japanese Knotweed which is becoming prevalent in British gardens.
In 2015, the World Health Organisation said glysophate “probably” caused cancer.
American agriculture giant Monsanto, which manufactures Roundup, is currently at the centre of a high profile lawsuit in California, where a group of US farmers claim the weedkiller gave them non Hodgkins’ lymphoma.
Lawyers have claimed Monsanto asked the court to ignore scientific studies that suggested a link between cancer and glyphosate.
Should the judge decide there is sufficient scientific evidence linking the product with the disease, Monsanto could potentially have to pay out millions in compensation and lose its flagship product used by millions around the world.