Passengers departing from an airport should be scrutinised to the same extent as when they arrive in a foreign country, a security expert has said.

Philip Baum, editor of Aviation Security International, said focus needs to switch from checking prohibited items are not being taken on planes to "assessing the intent of individuals".

Mr Baum said that an "intelligent response" is required, rather than the current "tick box" approach.

He made the comments after Foreign Secretary Philip Hammond warned airport security around the world would have to be upgraded if a Russian plane that crashed in Egypt last month is found to have been brought down by an Islamic State (IS) bomb.

Mr Baum told the Press Association: "That means more layers of security, where we use technology intelligently.

"We use different technologies for different types of people and we empower people to try and identify unusual behaviours in their colleagues, in passengers and in the crew."

He also highlighted the difference in the way airport security officials treat passengers before they board a plane, to the way passport control and immigration officers assess them once they have arrived at their destination.

"(Airport security) are not allowed to profile, they have to treat everybody the same," he said.

"Yet when you get off an aircraft in a foreign destination you go through immigration where they differentiate between passengers, you go through customs where they differentiate between passengers, and every day they are identifying people doing wrong, after they have got off an aircraft.

"Surely we should be using those same technologies before they get on an aircraft."

Matthew Finn, managing director of aviation security consultants Augmentiq, called for more attention to be paid to airport staff who operate in and around planes before they take off.

He asked: "Who are the people who have access to the aircraft? Where are they working? What are their associations? How much do we know about them? How often are they vetted?"

A "different culture" needs to be created in aviation security, Mr Finn said.

"People don't want to work in this industry," he claimed. "Kids aren't going through school saying 'I want to work in aviation security'.

"That is a sad indictment of our industry. We need to raise our game."

Mr Finn said that better airport security could have prevented incidents such as three schoolgirls from east London travelling to Syria to join IS.

The Bethnal Green Academy pupils - Shamima Begum, Amira Abase and Kadiza Sultana - disappeared from their homes in February and flew from Gatwick Airport to Turkey, before crossing the border into Syria.

"They were known to the police so therefore an alert could have been put out because they were deemed vulnerable.

"Yet they went through airport security, which is a government security check point, and they passed through unsuspected even though in any normal circumstances they should have been flagged," Mr Finn said.

"Aviation security should be able to perform that control function as well. We should be able to detect people and intervene, certainly if they are vulnerable."

Mr Finn also urged against the cost of upgrading security being passed on to passengers in large fare rises.

"I would like to think we can be smart about how we use resources, rather than simply adding costs on," he said.

"Security already has quite a burdensome effect on air transport in particular and certainly in the cost for passengers.

"I think it can be done more smartly, I think there's a role for government to play in using some of the capabilities that they have available to them a little bit more intelligently."