Reiterating close cooperation with Egyptian officials to determine the crash causes, French President Hollande said to dispatch aircraft and vessels to help Egyptian authorities to find debris that would "allow to know the truth."

British Foreign Secretary Philip Hammond on Thursday expressed his deep concern over the loss of EgyptAir flight MS804.

"Deeply concerned by missing EgyptAir. Can confirm British passport holder was on board and FCO (Foreign and Commonwealth Office) is supporting the missing passenger's family," he said on his Twitter account.

In a separate statement, he said: "My thoughts are with the family and friends of all those missing following the disappearance of EgyptAir's flight MS804."

He also confirmed that one British passport holder boarded the flight in Paris and FCO staff are providing support and assistance to the family.

"We are in close contact with Egyptian and French authorities and have offered the Egyptian authorities our support in their search and rescue efforts," he added.