Major US airlines that raised fares last week to offset high fuel prices have rescinded the increases to remain competitive with other carriers that did not match.

Delta Air Lines, American Airlines, United Airlines, Continental Airlines and Northwest Airlines each said on Monday that they withdrew the increases over the weekend.

The airlines raised their fares by USD$6 round-trip in some markets last week to combat high fuel prices. The increase was led by United on Thursday, but low-cost carriers (LCCs) failed to match it.

"The LCCs did not match the fare increase, therefore we rescinded to stay competitive with the LCCs," United spokeswoman Robin Urbanski said.

The airline industry has been battered by high fuel prices, which are directly linked to the cost of crude oil. Low-fare competition makes it hard for airlines to raise fares.

Crude oil futures have fallen more than 20 percent since August, but remain historically high and a burden for airlines. Oil traded at USD$58.29 a barrel on Monday afternoon, down $2.46 on the day.

The fact that the top five carriers at least attempted to raise fares last week bolsters the chance for another fare increase this year, said Terry Trippler, airline expert at travel club myvacationpassport.com.

"I think this was an indication that the legacies are in camp," Trippler said. "Now they have to hope the low-cost carriers are going to be in camp."