The world’s largest seed company, Monsanto Co, on Tuesday (24 May) turned down a US$62bn acquisition offer from Bayer AG, saying it was “incomplete and financially inadequate”, Reuters reports.

Monsanto did say that it was open to engage in further negotiations.

The rejection means Bayer must decide if it wants to raise its bid.

The original offer of US$122/share was criticised by some shareholders as already being too high, Reuters reported. Monsanto shares ended trading at US$109.3 in New York on Tuesday, much lower than the offer price.

Monsanto Chief Executive Hugh Grant said in a statement, “the current proposal significantly undervalues our company and also does not adequately address or provide reassurance for some of the potential financing and regulatory execution risks relating to the acquisition”.

Bayer said it looked forward to engaging in constructive discussions with Monsanto on the offer.

Although Monsanto gave no indication what price it would be willing to accept, analysts at JPMorgan suggested US$135 was more likely to be accepted.