Airline passengers travelling from Canada to the United States will face a new battery of "enhanced security measures" now required by the Department of Homeland Security.

The new measures will be enforced starting July 19 and include:

Enhanced overall passenger screening.

Heightened screening of personal electronic devices.

Increased security protocols around aircraft and in passenger areas.

The use of advanced technology, expanded canine screening and the establishment of additional pre-clearance locations.

WestJet and Air Canada are advising passengers to arrive at the airport at least two hours before their scheduled departure to accommodate the enhanced screening process.

All electronic devices larger than a smartphone will have to be removed from protective casing and fully charged for potential inspection.

U.S. cites terrorism concerns

"The United States and the global aviation community face an adaptive and agile enemy," says Homeland Security in a statement on its website announcing the changes.

"Terrorist groups continue to target passenger aircraft, and we have seen a 'spider web' of threats to commercial aviation as terrorists pursue new attack methods," it says.

In addition to the more thorough screening process, Homeland Security is also implementing "heightened security standards" for airports and aircraft.

The new measures will be required at approximately 280 airports around the world that offer flights to the United States.

Homeland Security says it may introduce additional security restrictions on any stakeholders who do not fully implement the changes.