U.S President George Bush vowed to "protect the flying public," as he blocked a looming strike by Northwest Airlines mechanics for 60 days and said he would not let other labor disputes slow commercial flights in America.

WASHINGTON -- President Bush is prepared to act to prevent a strike at any of the major U.S. airlines if authorized to do so by the National Mediation Board, the White House said Tuesday.

"He is prepared to act if he has the authority to act," White House spokesman Ari Fleischer told reporters. The National Mediation Board is a federal agency that mediates labor-management disputes in the U.S. airline and railroad industries, according to a wire service.

"The president's concern is that the traveling public not be disrupted and that the economy, particularly in this fragile time, not be given any additional setbacks," Fleischer said.

Bush acted Friday to avert a threatened strike by Northwest Airlines Corp. mechanics for 60 days and said he would not let other labor disputes slow commercial flights in the country.

Bush's move effectively prevented any strike until May 12, by creating a three-member presidential emergency board that will produce settlement recommendations. The federal government has stepped into a number of railroad disputes, but the Bush-ordered emergency board is only the second formal White House intervention in a major airline contract dispute in 35 years.

The flight attendants' union at No. 1 airline United Airlines has alerted members it may strike if it is not taken into account in merger talks with US Airways.

Delta Air Lines -- the No. 3 U.S. airline -- and the Air Line Pilots Association are embroiled in a contract dispute.