Security is being increased across British airports after the United States called for heightened precautions.
The Department for Transport said the extra measures were not expected to cause "significant disruption" to passengers, and the threat level remains unchanged. A spokesman said:
The UK Government keeps aviation security under constant review in conjunction with international partners and the aviation industry. We have taken the decision to step up some of our aviation security measures. For obvious reasons we will not be commenting in detail on those changes.
The majority of passengers should not experience significant disruption. There will be no change to the threat level, which remains at substantial.
The safety and security of the public is our paramount concern.