Sovereign Bancorp Inc., the second-biggest U.S. savings and loan and one of the biggest banks in Rhode Island, plans to raise about $1.5 billion in capital as the company tries to rebound from losses last year.

The lender will sell $1 billion in common stock and approximately $500 million in fixed-rate subordinated notes to build a “cushion” in case the economy slows more, Sovereign spokesman Ed Shultz said yesterday.

“We’re not taking this action from a position of stress,” Shultz said. “The board and the company decided to be proactive and prudent.”

The new funds will add to the more than $245 billion raised by the world’s biggest banks and securities firms after losses tied to mortgage and debt markets. Philadelphia-based Sovereign reported a $1.3-billion loss last year. The company reduced some lending as defaults increased, and omitted its quarterly dividend in January. Shultz said Sovereign was not asked by regulators or ratings agencies to raise capital.

The $1.5 billion “should be sufficient to get the company through this crisis,” RBC Capital Markets analyst Gerard Cassidy said in an e-mail. “Raising capital at these depressed levels tells me it was done due to necessity.”

Sovereign said that its two biggest shareholders are planning to boost their investment in the company.

Once at loggerheads over control of the Philadelphia thrift, Spain’s Banco Santander S.A. and Relational Investors LLC, of San Diego, plan to participate in Sovereign’s $1-billion common stock offering, according to a Securities and Exchange Commission filing.

Madrid-based Santander, which own 24.9 percent of Sovereign, and Relational, which owns 6.3 percent, did not disclose how much they plan to invest.

Santander is expected to buy up enough shares to keep its ownership stake steady, since a stock offering would dilute holdings. If its ownership stake went above 24.9 percent, Sovereign would need shareholder approval.

“It certainly brings much needed capital,” said Rick Weiss, an analyst at Janney Montgomery Scott. “They’re still well-capitalized, but it’s thin. If the economy does tank ... $1 billion in capital can go a long way.”

Weiss said Santander’s move also means that the Spanish banking giant won’t be buying the rest of Sovereign in the short run: “This kind of allows them to keep their options open for now.”

The housing market has taken a heavy toll on the banking industry. While not directly affected by subprime mortgages, Sovereign has seen loan defaults rise. It has stopped issuing auto loans in states where defaults mounted and suspended the company dividend.

The Spanish bank will take part in the offering in proportion with its holdings, an official spokesman said. He declined to be identified by name.

Relational, the activist fund led by Ralph Whitworth, is also expected to participate in the sale, the lender said in a regulatory filing.

Sovereign rose 32 cents, or 4.1 percent, to $8.18 in New York Stock Exchange composite trading, but has fallen 28 percent this year. Matthew Kelley, an analyst at Sterne Agee & Leach Inc. in New York, said last week he expected the bank to price shares in a fundraising at about $6.

The lender projected in a regulatory filing its Tier 1 ratio may be 9 percent to 9.42 percent by December of this year. A bank is considered well-capitalized by regulators at 6 percent. The lender reported that nonperforming loans rose 73 percent as of March 31 from a year earlier to $417.8 million.

“Although we view the company’s capital raise as a positive development for Sovereign, we believe that the company’s performance will continue to be pressured,” Standard and Poor’s analyst John Bartko said in a note, adding that lender’s credit rating won’t be affected by the new capital. Fitch Ratings also affirmed the lender’s rating.

Lehman Brothers Holdings Inc. is managing the sale of Sovereign’s common stock and will have the option to buy as much as $150 million more shares in case of strong demand, the company’s statement said.

UBS AG analyst Matthew O’Connor said April 24 that Sovereign was the most likely of the 16 banking companies he tracks to need a “large amount of capital.”

Seattle-based Washington Mutual Inc., the largest U.S. savings and loan, said last month that it would raise $7 billion in a deal struck with TPG Inc. Sovereign is the second-largest publicly traded savings and loan by assets.

Santander’s initial purchase of a 19.8 percent stake in Sovereign in May 2005 led to the ousting of its then-chief executive officer Jay Sidhu.

With Associated Press reports