The Donald Trump administration is believed to have issued a circular banning electronic devices larger than cellphones on flights to and from a few countries. The directive was issued to a few airlines on Monday based on an intelligence report about a possible threat, reported Reuters. The Department of Homeland Security is expected to make an official announcement on Tuesday.

According to the notice, people travelling by certain foreign airlines will now have to check in their laptops, iPads, Kindles and even cameras larger than mobile phones. Medical devices are excluded from the ban. The rule is not applicable to American airlines.

While The Guardian said the restriction was imposed on people travelling to and from a few West Asian countries, a report by Independent said that several North African countries were affected as well. Saudia Airlines and Royal Jordanian airlines tweeted about the circular informing their passengers about the new rule.

However, the circular does not seem to be very clear or specific. Though it bans large electronic devices from flight cabins, it does not say anything about electronic flight bags. These are used by flight crew to display maps and documentation, usually on an iPad, reported The Guardian. The new rule will be effective from March 21.

This comes even as Trump’s repeated efforts to close the US borders for people from Muslim-majority countries have been thwarted multiple times by the country’s courts, which had also stayed his contentious travel ban orders in the past.