Syngenta AG, target of an unwanted $45 billion takeover approach by Monsanto Co., said its U.S. suitor has failed to convince it of the merits of a merger and is repeating the “same inadequate price” with a flawed view of the execution risks.

The only change in Monsanto’s proposal since the first offer from April 18 is a “wholly inadequate” breakup fee of $2 billion, the Basel, Switzerland-based maker of agrochemicals and seeds said in a statement on Monday. The U.S. company’s next move may be to formalize its approach and possibly take it directly to shareholders, Berenberg analyst John Klein said.

Frustration is creeping into Syngenta’s demeanor, as the company faces the twin challenges of a detrimental effect on business of a prolonged pursuit and widespread expectations among investors of a higher offer. Chief Executive Officer Mike Mack has trodden a careful path since the initial approach, acknowledging the need to do proper due diligence on Monsanto’s plan to create an agricultural-products powerhouse, while emphasizing the prospects the company has going solo.

“It’s not the end of the takeover saga,” said Markus Mayer, an analyst at Baader Bank AG, who has a “buy” rating on Syngenta. “The second offer was not a big change – just a break-up fee. It shows that Monsanto is still interested.”

Syngenta shares fell as much as 2.5 percent and traded 0.7 percent lower at 409.80 francs as of 3:01 p.m. in Zurich. That values the company at 38 billion francs.

Turning Hostile

Monsanto is seeking to jump start talks on combining its leading franchise for genetically modified seeds with the world’s largest maker of agricultural chemicals. The break-up fee would be payable if Monsanto is unable to obtain global regulatory approvals by selling all overlapping businesses. It’s also looking to obtain some due diligence information to help refine and quantify the upside of a merger.

“The statement suggesting a review of the offered price if due diligence confirms a higher valuation is adequate will put further pressure on Syngenta’s board to engage and offer this data,” Berenberg’s Klein said in a note. “We still do not expect Monsanto to increase its offer substantially. The next step should be a formal – potentially hostile – offer.”

Such a move could come before a scheduled earnings release on June 24, Klein said.

Syngenta rejected the 449 francs-a-share bid, with 45 percent payable in cash, saying it undervalued the company and doesn’t sufficiently compensate for antitrust risks. Syngenta would consider entering talks if Monsanto raises its offer and adds a multibillion-dollar termination fee in the ballpark of 10 percent of the purchase price, people with knowledge of the situation said last week.

Fruitless Meetings

“Hostility between management teams is not helpful,” said Christian Faitz, an analyst at Kepler Cheuvreux. “I think they could go hostile, but it would have been much easier if they had just upped the offer. They could have gotten the deal done.”

Syngenta advisers met with counterparts representing Monsanto on three separate occasions since the rejection, and each time the Swiss company was left with doubts that Monsanto was making serious efforts to address regulatory risks, the company said Monday, adding that its suitor continues to gloss over fundamental transaction risks.

Baader’s Mayer said Monsanto will have to sweeten its bid to at least the 500-franc mark – the analyst’s target price – or change the equity or cash components of the deal.

Urging Cooperation

“It is disappointing that Syngenta has not engaged in substantive discussions about the many benefits of this combination,” Monsanto Chairman and Chief Executive Officer Hugh Grant said in a statement.

While reiterating he’s committed to the deal, Grant said his “preference” is to work with Syngenta “at this stage,” urging board members to engage in the process.

Monsanto, based in St. Louis, has pledged to sell Syngenta’s seed and genetically engineered traits as well as any overlapping crop chemicals to win regulatory approval. Chemicals that would be sold include Syngenta’s glyphosate and acetochlor herbicides. It also suggested domiciling the enlarged group in the U.K., which would lessen the negative perception of lowering its tax burden via a move to Switzerland.

Syngenta said it’s at the start of a “significant upturn in innovation” that will help margins climb to 24 percent to 26 percent by 2018. Monsanto’s bid represented a 43 percent premium to Syngenta’s share price at the close on April 30, just before Bloomberg News reported the proposal.