"We are responding to questions from the Egyptians regarding the engines," Weiss said when asked if the NTSB was involved in the crash investigation.

The spokesperson further characterized the US-Egyptian relationship in the inquiry as "a positive one."

US officials reported earlier in the week that the NTSB was considering putting together a dispatch team to look at the physical evidence from the Metrojet Flight 9268 crash, but that the agency was still waiting on details regarding when and where the plane’s engines would be brought for examination.

The Airbus A321, operated by Russia’s Kogalymavia, crashed in the Sinai Peninsula after takeoff from the Egyptian resort of Sharm el-Sheikh en route to St. Petersburg on October 31, killing all 224 people on board.