U.S. authorities are planning to ban passengers traveling on certain U.S.-bound foreign airline flights from carrying bigger electronic devices into the cabin in response to an unknown terrorism threat, U.S. officials told Reuters on Monday.

The new rule will be announced as early as Monday by the Department of Homeland Security, the officials said, adding that it had been taking this as a consideration since the U.S. government was alerted of a threat several weeks ago.

The source said the rule would impose on several foreign airlines flying from about different countries, including some from the Middle East, and also airlines based in Jordan and Saudi Arabia. The officials did not specify the other countries as of now.

The officials said no American carriers were impacted by the ban, which is applicable to devices bigger than a cell phone without further explanation. Passengers would be allowed to carry bigger devices in their checked luggage such as tablets, laptops, and cameras.

Royal Jordanian Airlines said in a tweet on Monday that U.S.-bound passengers would be banned from carrying most electronic devices aboard aircraft starting Tuesday upon the execution the new rule set by U.S. officials, including those transiting through Canada. Passengers are still allowed to carry cell phones and approved medical devices.

Al Riyadh newspaper, a friend to the Saudi government, reported that the civil aviation authority had informed "airlines flying from the kingdom's (Saudi) airports to U.S. airports of the latest rules from U.S. security agencies in which passengers must put laptops and tablets" in checked in baggage.

Saudia Airlines confirmed in a tweet that U.S. transportation authorities had banned carrying larger electronic devices in hand-carry luggage. A spokesman for the U.S. Department of Homeland Security, David Lapan, said the agency has "no comment on potential security precautions, but will announce when time is right."