Just six days after announcing its new lower-priced business fares, Northwest Airlines said Wednesday it was reducing the markets where it offers the BizFlex pricing.

``We're taking it out of competitors' hubs,'' said Kathy Peach, spokeswoman for the nation's fourth-largest airline. The decision was made in response to ``competitive reaction'' to the new fares, she said.

That means the fares -- which are 40 percent cheaper than unrestricted full coach walkup fares and do not require a Saturday night stay -- are not available to business travelers out of Chicago; Denver; Newark, N.J.; Dallas; Atlanta; and other airline hubs unless the traveler is headed to one of Northwest's hubs in Minneapolis-St. Paul, Detroit or Memphis, Tenn.