By Matthias Rieker Of DOW JONES NEWSWIRES NEW YORK -(Dow Jones)- Earnings at several large regional banks improved at a healthy clip during the first quarter, but the lackluster economy frustrated some bankers who said they were ready to use more of their cash to make new loans. U.S. Bancorp (USB), one of the nation's largest regional banks, reported a 55% jump in profit from a year earlier, to $1 billion, while earnings at Comerica Inc. (CMA), a large commercial lender in the South and the Midwest, rose 98%, to $103 million. Both banks have grown since the financial crisis abated, but largely through acquisitions and luring customers from other banks, rather than making more loans to their existing customers. Both said companies continue to park cash in bank deposits rather than making business investments, dampening the need for loans. So while loan books grew some, lackluster demand for loans continues to reflect an uncertain economy and clouds the banking industry's revenue outlook. "We have seen the economy slow a bit in the second half of the first quarter, things are actually not as positive as we thought they would be," U.S. Bancorp Chairman and Chief Executive Richard Davis said during a conference call with investors. "We'll know in a couple weeks whether or not we're off to a decent 2011." Losses from bad loans, meanwhile, continue to abate, and bank earnings benefit from setting aside less capital for future delinquencies. Regions Financial Corp. (RF), a big lender in the Southwest that is struggling to recover from the real-estate meltdown, reported a $69 million profit, compared with a $196 million loss a year earlier. And Zions Bancorp (ZION) of Salt Lake City said late Monday its results swung to earnings of $52.8 million from a $60.5 million loss, its first quarterly profit in two and a half years. Clearly the demand for new loans is nowhere near the capacity banks have to lend. Bankers blamed, in part, the natural disaster in Japan, which disrupted the supply chain of manufacturers worldwide, for the lackluster demand. Further, continued unrest in North Africa and the Middle East, "and increasing food and energy prices here in the U.S. appear to be dampening confidence," Comerica Chairman and Chief Executive Ralph Babb Jr. said during a conference call with investors. Comerica reported more demand from energy companies and Babb said demand particularly in Texas has accelerated. Overall, bankers said those companies that are taking out new loans are manufacturers. U.S. Bancorp's Davis expressed frustration at the pace his bank can make loans. "We are disappointed we're not keeping [loan growth] at that pace" the bank set in previous quarters, he said. Demand "is wholly insufficient as far as I'm concerned given the money we have to deploy back into loans." At U.S. Bancorp, loans grew 1% from the previous quarter, to $181 billion, but had grown about 2% in previous two quarters. "It is not doom and gloom," but expectation are more measured now, CEO Davis said. The bank bought securities instead to invest its capital. Its revenue rose 4.6%, to $4.5 billion. Comerica said revenue fell 3% from the fourth quarter because loans ran off faster than the bank could make new ones. Revenue fell 1.2% from a year earlier, to $602 million. The bank's loan book shrank 4.1% to $39 billion. Rene Jones, chief financial officer of M&T Bank Corp. (MTB) of Buffalo, N.Y., another healthy bank, told Dow Jones Monday that loan demand wasn't robust. KeyCorp (KEY) of Cleveland said Monday business loan demand improved but was overshadowed by real estate loans that run off its books. --By Matthias Rieker, Dow Jones Newswires; 212-416-2471; firstname.lastname@example.org --David Benoit contributed to this article.