The Charlotte-based bank's move adds to similar actions by Mastercard Inc. and PayPal Inc. Though previous moves have prompted reprisals by hackers, Bank of America's site is as well-protected as they come, security experts say.
Its site was problem-free through midafternoon Saturday.
"This decision is based upon our reasonable belief that WikiLeaks may be engaged in activities that are, among other things, inconsistent with our internal policies for processing payments," the bank said in a statement Saturday. The move was first reported by The Charlotte Observer.
Earlier this month, Internet "hacktivists" operating under the label "Operation Payback" claimed responsibility in a Twitter message for causing technical problems at the MasterCard website after it ended its relationship with WikiLeaks. PayPal saw its website subject to an attack that slowed it down but did not significantly affect payments.
Bank of America's website offers access to customer accounts through its home page, but it could be a tough nut for hackers to crack, security experts say.