Northwest Airlines

(NWAC)

is boosting ticket prices by $10 each way on longer flights and $5 on flights shorter than 1,000 miles.

The move was prompted by rising fuel prices and "the fact that we're coming into a historically strong travel period," said Kurt Ebenhoch, a spokesman for the airline. The increases apply to all Northwest flights in the U.S. and Canada.

It remains to be seen whether other U.S. airlines, which also are incurring higher fuel expenses, will follow Northwest. Several attempts by large carriers to institute fuel surcharges last year failed to stick. Crude oil for April delivery closed up 22 cents at $51.39 a barrel, after breaking $52 earlier in the session.

Ebenhoch declined to comment on whether Northwest expected other airlines to institute similar fare hikes.

Northwest shares finished Thursday's session up 8 cents, or 1.2%, at $6.74.