United Technologies chief executive Gregory Hayes said Friday that Honeywell’s recent $90 billion offer for the industrial group “grossly undervalues” the company.

Hayes reiterated his rejection of the last week’s bid after Honeywell revealed the details publicly for the first time on Friday, including the price it had proposed.

Honeywell offered the equivalent of $108 a share in cash and stock for United Technologies in a proposal to bring together two major players in the aerospace and industrial technology industry with a combined $97 billion in annual sales.

Honeywell said a tie-up could result in $3.5 billion in annual cost savings, lower margins and stronger earnings growth.

Hayes originally nixed the deal on Monday, saying it would not pass muster with antitrust regulators because the two compete in many areas.

He reiterated that position on Friday, saying the company believes regulators would likely block the merger. Or if they did not, he said, “the regulatory delay, required divestitures, and customer concerns and concessions would ultimately destroy shareholder value far beyond any synergies.”

But he also argued that the offer was too low.

“Honeywell’s proposal grossly undervalues UTC and overstates potential synergies. Effectively Honeywell’s proposal is a leveraged buyout of UTC using UTC’s own strong balance sheet.”

United Technologies shares had risen for two days amid speculation a deal was still possible, and after its announcement Friday they fell to $97.00, down 1.1 percent.

Honeywell shares lost 0.8 percent at $103.42.