A group of Akzo Nobel shareholders led by hedge fund Elliott Advisors who support a merger of the two companies have been pushing for talks, but Akzo said in a statement it would not engage in discussions with the U.S. company.

Dutch paint maker Akzo Nobel on Monday rejected a third takeover proposal from larger U.S. rival PPG Industries , valued at 26.9 billion euros ($29.51 billion), saying it undervalues the company, faces antitrust risks, and does not address other concerns such as "cultural differences."

PPG must now decide whether it will move to a formal bid ahead of a June 1 deadline under Dutch securities laws without support of Akzo's boards.

"AkzoNobel has concluded its own strategy, presented on April 19, 2017, offers a superior route to growth and long-term value creation and is in the best interests of shareholders and all other stakeholders," Akzo said in a statement.

PPG's latest offer in cash and shares on April 24 values Akzo's stock at around 96.75 euros per share. That's a 50 percent premium to where Akzo shares traded before PPG's interest became known on March 9.

Akzo's shares closed Friday at 79.40 euros per share, signaling investors have strong doubts PPG's pursuit will be successful.

Elliott Advisors, which holds a 3.25 percent stake, had joined with other institutional investors representing more than a 10 percent stake to convene an extraordinary shareholders' meeting to debate the dismissal of Chairman Antony Burgmans over the company's refusal to enter talks.

Although such a request is allowed under Dutch law, Akzo refused, saying it would not be in the company's best interest.