The European Commission is scrutinizing the impact the deal will have on competition in pesticides and seeds markets.
On Tuesday, German pesticides and drugs makers Bayer said, it would need some more time to complete its $66 billion takeover of U.S. seeds group Monsanto. Earlier Bayer had said it expected to wrap up the acquisition by the end of 2017.
Incidentally, the European Commission is scrutinizing the deal with a deadline of January 8.
Bayer has said it has asked the regulator for an extension for January 22.
Last month the European Commission started an in-depth investigation into the takeover citing worries of how the deal will impact competition in pesticides and seeds markets.
Bayer, who is holding a media event on its Crop Science business on Tuesday, said it expects the division to face volatile global markets for the remaining half of 2017, and has forecast a return to growth in 2018.
In June, Bayer had warned, the poor sales at crop protection distributors in Brazil would significantly impact its 12 months earnings.