PITTSBURGH — Alcan Inc. rebuffed a hostile takeover bid by aluminum competitor Alcoa Inc., dismissing the $27 billion offer as inadequate. But analysts say the move was expected and is likely part of a plan to fetch a sweeter deal.

"It's a little like a mating dance, and the whole idea is to eventually get a better price," said Charles Bradford, an industry analyst with Bradford Research/Soliel Securities in New York.

Alcan's board recommended to shareholders Tuesday that they reject Alcoa's May 7 bid because it fell short of the company's value and is not in the best interests of investors, Chairman Yves Fortier said in a statement.

"It does not adequately reflect the value of Alcan's extremely attractive assets, strategic capabilities and growth prospects, does not offer an appropriate premium for control of Alcan, and is highly conditional and uncertain," he said.

The companies, Fortier said, have "fundamentally different approaches and track records in creating shareholder value."

Alcoa spokesman Kevin Lowery said his company, based in Pittsburgh with executive offices in New York, was reviewing Alcan's lengthy response, which was filed with the Securities and Exchange Commission.

"We continue to believe that our offer is full, fair and provides attractive value to Alcan shareholders," he said.

Among the reasons for the board's decision, Alcan said, was that the offer represents a discount to the trading price of Alcan shares, with a total value that will vary with the price of Alcoa shares.

The bid includes $58.60 a share in cash and 0.4108 of an Alcoa share for each share of Alcan.

At Alcoa's closing price Tuesday of $38.95, the bid stands at $74.60 per share, below Alcan's closing price of $81.03. Alcan shares gained 3.1 percent to $83.50 in after-hours trading Tuesday, while Alcoa shares rose 1.8 percent to $39.64 after hours.

Alcoa launched its cash and stock bid for Montreal-based Alcan after almost two years of private talks failed to produce a negotiated agreement.

Dick Evans, Alcan's president and chief executive officer, said the company had remained disciplined in talks with Alcoa, insisting on safeguards for shareholders before engaging in substantive negotiations.

"Despite two years of approaches by Alcoa, at no time was Alcan presented a compelling proposal — either in terms of economics, structure or conditionality — that was in the best interests of our shareholders," he said.

According to Alcan, a financial adviser also said in a written report to the company's board that Alcoa's proposal was financially inadequate. Alcan said its advisers on the offer included Morgan Stanley and UBS.