Bayer AG on Friday said it has agreed to sell parts of its crop-science business to rival BASF BAS, -3.03% for 5.9 billion euros ($6.98 billion), a bid to assuage regulators as the German chemical conglomerate seeks approval for its $57 billion acquisition of U.S. seed maker Monsanto Co.

Bayer BAYN, -3.42% said it would use the net proceeds from the transaction to partially refinance the purchase of Monsanto US:MON , a deal struck last year that is set to create an industrial powerhouse and tilt the German company heavily toward agriculture in a long-range bet on high-tech crops.