NEW YORK (The Deal) -- Swiss crop-science company Syngenta (SYT) said Tuesday it would only contemplate a takeover proposal if it was highly likely to close and accompanied by a hefty breakup fee.

The Basel company made its wishes known via YouTube through an interview with Chairman Michel Demaré, designed as a response to unsolicited bidder Monsanto's (MON) European lobbying efforts in support of its spurned Sfr41.7 billion ($44.5 billion) bid.

Demaré said he had taken to YouTube to communicate "concurrently with all shareholders and the other stakeholders" the reasons it rejected Monsanto's May offer. The interview was posted two weeks after Syngenta rejected a revised bid, which the St. Louis suitor had sweetened with a $2 billion breakup fee. On Tuesday Demaré called the tweaked proposal a "copy paste" of the original bid.

Syngenta has from the outset said the Monsanto bid is too low and doesn't properly factor in the huge antitrust risks of attempting to unite the world's No. 1 seeds group with the leader in crop protection and the No. 3 in seeds.

"A serious proposal to buy Syngenta has to be made at full and fair value, it has to recognize for shareholders the inherent combination benefits and it has to provide a high degree of certainty that the transaction will be closed including compensation in case the deal fails, be it for antitrust reasons or for any other reason," said Demaré. "Absent these parameters I think the board would be irresponsible even to accept to negotiate under such terms."

He said Monsanto's $2 billion breakup fee wouldn't cover the "huge commercial and organizational consequences" of a failed deal. The fee equated to Sfr25 per share, he added, and "will not even start covering this risk."

He also professed himself "confused" about whether Monsanto's offer was still predicated on the creation of a holding company with its tax domicile in the U.K. and said Syngenta wouldn't want to leave Basel, and its 250-year heritage in the Swiss city.

"I have a hard time to see how a U.K. setup could be more competitive, and especially for shareholders," he said.

Syngenta American depositary receipts were off 0.5% to $86 while Monsanto stock is off 0.5% to $113.79.

Some analysts have speculated that Germany's BASF (BASFY) and Bayer (BAYRY) as well as Dow Chemical  (DOW) and DuPont (DD - Get Report) and even China National Chemical may enter the bid fray.

Monsanto's stock-and-cash offer was worth Sfr449 per share as of May, and includes 45% cash. The U.S. company reports third-quarter results on Wednesday and analysts and investors will be watching closely for any commentary on the bid.

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