VeriFone Systems Inc. announced Wednesday an unsolicited bid to buy rival Hypercom Corp. at $5.25 per share.

The combination, if a deal is completed, would link the two main terminal makers in the United States, though analysts were skeptical that Hypercom would acquiesce.

"There are significant operating synergies that will enhance product development and sales expenses in many markets," especially Europe, Douglas G. Bergeron, VeriFone's chief executive, said in a conference call. "We see this as a great opportunity to expand our footprint in continental Europe."

VeriFone said the price was a 69% premium over Hypercom's average share price for the 30 trading days prior to its offer.

Bergeron said that he would pursue the acquisition even if Hypercom's board rejected the offer. "We are committed and resolute to seeing this transaction through to a successful closing."

A Hypercom spokesman said the board was reviewing the offer.

"I would, right now, be somewhat skeptical that it would get passed," said Robert J. Dodd, an analyst at Morgan Keegan & Co. Inc.

He noted that the French terminal maker Ingenico SA offered to buy Hypercom in 2008 at $6.25 per share, but the Scottsdale, Ariz., vendor rejected the offer, saying then that it undervalued the company. Ingenico later withdrew its bid after Hypercom purchased another payments company, the e-Transactions unit of Thales SA.

Dodd said that Hypercom would help VeriFone bolster its presence in Western Europe, though there would be hurdles.

"This is not a zero-sum game, when you buy a competitor," he said. "Where you overlap you lose market share. There generally has to be a pretty compelling case for some kind of synergy, on cost or something like that, or product set."

Bergeron said the deal would be funded with cash "on hand" and "new committed financing."

VeriFone has hired JPMorgan Securities LLC as financial advisors, and Sullivan & Cromwell LLP as counsel in connection with the proposed transaction.

Hypercom shares closed Wednesday at $4.23, up 1.44% from Tuesday.

However, news of the offer came after the trading session closed, and its shares surged in after-hours trading, rising 44%, to $6.05.

According to Yahoo Finance there are 54.02 million outstanding shares of Hypercom, valuing the deal at $283.61 million.