Banc One Corp. and Wells Fargo & Co. have agreed to assist American  Express Co. in a high-profile campaign to establish itself as "the money   source for small business."   
The banking companies will underwrite pre-approved,  unsecured lines of credit that American Express will offer to U.S. business   customers, Amex announced Tuesday.   
  
Buying into American Express' desire for closer cooperation with banks,  Banc One and Wells view the travel-and-entertainment company's customers as   an attractive lending outlet.   
"We know how to underwrite and monitor and control credit, and they know  how to market the heck out of a product," said Banc One chief   communications officer John Russell.   
  
But the cooperation was restricted to that deal, as  American Express announced other corporate credit initiatives on its own.   Also on Tuesday, it turned up the legal heat on Visa International, filing   legal complaints in several Latin American countries - and a request for an   antitrust investigation in Puerto Rico - to forestall adoption of a policy   that would prevent banks in that region from working with American Express.         
Visa's Latin American board is expected to vote on the proposal next  month. 
"We want to defeat the bylaw before it is formalized and ensure maximum  awareness of this issue," said American Express spokeswoman Elisabeth   Coleman.   
  
At a New York news conference on the small-business programs, American  Express said it will offer two proprietary cards - a Gold Corporate Optima   card and a corporate version of the Delta SkyMiles Optima card - each with   credit lines of up to $20,000, at an introductory interest rate of 8.9% for   six months.       
The New York-based card and travel giant also said it was launching a  lease-financing program for the purchase of business equipment. 
Even as it works with two prominent superregional banking companies,  American Express is becoming more competitive against banks and their card   associations - Visa and MasterCard - in the rush to serve business owners   and entrepreneurs.     
American Express vice chairman George L. Farr told reporters, "We have a  natural advantage over banks, who don't have an understanding of the needs   of small businesses."   
  
"It used to be that you knew who your enemies are," said Joel Friedman,  a managing director with Andersen Consulting and a longtime consultant to   Visa International. "Today, the person you partner with is also your   competitor, and that's the case between American Express and a number of   banks."       
For American Express, the latest set of initiatives follows a 10-year  effort to serve small businesses mostly through its traditional corporate   charge card program and the Optima credit card.   
"This is no flash-in-the-pan strategy," Mr. Carr said.
Amex said Banc One and Wells Fargo will underwrite lines of credit from  $5,000 to $50,000, which will be available on a pre-approved basis to   existing American Express small-business charge card clients.   
The credit lines will be priced with competitive interest rates and  accessible by check, so they can be used to pay for virtually any type of   business expense, Amex said.   
Stanley W. Anderson, a corporate-card expert who is  president of Denver-based Anderson & Associates, said American Express'   small-business initiatives represent a step toward its goal of more   alliances with banks - itself a throwback to an earlier era when American   Express marketed gold cards on which banks provided the credit lines.       
Because Visa and MasterCard have close ties to Banc One and Wells Fargo,  those banks' involvement in the American Express strategy should be of   concern to the card associations, Mr. Anderson said.   
"American Express has picked the plums of each of the card  associations," he said. 
Lisa Fickenscher contributed to this report.