In March the US banned cabin laptops to and from eight mostly Muslim nations, fearing bombs may be concealed in them.

The new measures require enhanced screening of passengers and electronic devices in 105 countries.

Airlines have 120 days to comply or could face a ban on carrying all passenger electronics.

They could even be denied the right to fly into the US.

Homeland Security Secretary John Kelly spelled out the new measures on Wednesday, saying: "Make no mistake: our enemies are constantly working to find new methods for disguising explosives, recruiting insiders, and hijacking aircraft.

"We cannot play international whack-a-mole with each new threat. Instead, we must put in place new measures across the board to keep the travelling public safe and make it harder for terrorists to succeed."

The new measures, which Mr Kelly said would not be the last, include:

• Enhanced overall passenger screening
• Heightened screening of personal electronic devices
• Increased security protocols around aircraft and in passenger areas
• Expanded canine screening

The measures are vague on specifics in terms of operational application, but will cover 280 airports and 180 airlines, affecting an average of 2,100 flights a day, carrying 325,000 passengers.

Airlines will be breathing a sigh of relief on the laptop issue, as many feared it might deter passengers, particularly high-fare-paying business customers, from travelling.

Mr Kelly had raised fears of a wider ban late last month, telling Fox News he was still considering it.

Homeland security officials said that even the airports included in the original laptop ban could have it lifted if they complied with the new regulations.

Devices "larger than a smartphone" are currently not allowed in the cabins of flights from Turkey, Morocco, Jordan, Egypt, the United Arab Emirates, Qatar, Saudi Arabia and Kuwait.

The UK issued similar rules for flights from six countries.

Air travel safety experts have warned there is a greater risk of lithium battery fires going unchecked if large electronic items are left in the hold.