A picture taken from southern Israel near the border with the Gaza Strip on December 3, 2023, shows an Israeli military helicopter flying over the Palestinian enclave.AFP
The UK has said at least 12 British nationals were killed on October 7 and that a further five are still missing.
However, it has not been confirmed how many are being held.
London did not reveal when its military surveillance flights over the territory would start but stressed they would be unarmed and focused only on captive recovery.
"In support of the ongoing captive rescue activity, the UK Ministry of Defence will conduct surveillance flights over the Eastern Mediterranean, including operating in air space over Israel and Gaza," it said in a statement.
"Surveillance aircraft will be unarmed, do not have a combat role, and will be tasked solely to locate captives," the ministry added.
"Only information relating to captive rescue will be passed to the relevant authorities responsible for captive rescue."
UK government minister Victoria Atkins told the BBC on Sunday that the aircraft to be utilised were "unarmed and unmanned drones".
Alongside the United States, the UK in October deployed various military assets to the eastern Mediterranean to deter "any malign interference in the conflict".
That included maritime patrol and surveillance aircraft as well as a Royal Navy task group moving to the region, the defence ministry said at the time.