Airlines are adding flights and hiring additional staff in preparation for a jump in demand as economies open up and vaccination coverage improves.

United said it had flown five times as many passengers during the fourth of July travel period than it did last year. The U.S. carrier expects the trend to remain for the rest of the year.

Smaller rival Spirit Airlines Inc said on Thursday it would resume all international flights, including routes to some Central American and Caribbean destinations, from Orlando.

Shares of United, which last month unveiled its largest-ever order for Boeing Co and Airbus SE jets, were up 1.6% premarket.

(Reporting by Abhijith Ganapavaram in Bengaluru; Editing by Krishna Chandra Eluri)