US 'Reviewing Steps' to Enhance Security for US-Bound Flights From 'Certain Foreign Airports'

— -- The Obama administration is reviewing "a number of different steps" to enhance security for flights bound for the United States from "certain foreign airports," White House Press Secretary Josh Earnest said today.

His comments come one day after the United Kingdom's decision to end U.K. flights to Egypt's Sharm el Sheikh airport for the foreseeable future, following a Russian jet that crashed near the airport this weekend that "may well have been brought down by an explosive device," according to British officials.

Earnest did not say what the "different steps" might be to enhance security for commercial flights, but said the steps would be announced by the Department of Homeland Security.

"When we develop those additional measures we work closely with [the airline] industry and our international partners to make sure they are properly and effectively implemented," Earnest said.

In response to British Prime Minister David Cameron's use of the word "bomb" when discussing the possibility of a terrorist bomb bringing down the Russian plane, Earnest said today, "At this point we don't have enough information to make our own determination about what exactly occurred. But we do have enough information at this point to not rule out the possibility of terrorist involvement."

The cause of Saturday's crash in the Egyptian desert remains undetermined and the black boxes are still being analyzed.

U.S. Defense Secretary Ash Carter told ABC News overnight that a bomb is a "possible reason" for the crash, but said he "understand[s] that there are other hypotheses."