The UK will conduct surveillance flights over Israel and Gaza as part of hostage rescue efforts.
The Ministry of Defence said the surveillance aircraft “will be unarmed, do not have a combat role, and will be tasked solely to locate hostages”.
“Only information relating to hostage rescue will be passed to the relevant authorities responsible for hostage rescue,” the ministry said in a statement.
The flights will take place over the eastern Mediterranean, including operating in air space over Israel and Gaza.
The MoD said the UK government had been “working with partners across the region to secure the release of hostages, including British nationals, who have been kidnapped” since the Hamas attacks on 7 October.
“The safety of British nationals is our utmost priority,” it said.
UK military was deployed to the eastern Mediterranean the week after the 7 October attacks, with RAF aircraft and Royal Navy ships sent to the region.
That was bolstered last week with the UK saying it would send one of its most lethal warships to the Gulf to deter growing threats to shipping from Iran and Iranian-backed groups.
The MoD’s announcement came as US vice president Kamala Harris called on Israel to do more to protect civilians.
She reiterated America’s stance that Israel has a legitimate military objective against Hamas, but said “too many innocent Palestinians have been killed”.
“Frankly, the scale of civilian suffering, and the images and videos coming from Gaza are devastating.”
Ms Harris was speaking at COP28 in Dubai, where she also laid out broad American objectives for when the war ends.
She told the Egyptian president that “under no circumstances will the United States permit the forced relocation of Palestinians from Gaza or the West Bank, the besiegement of Gaza, or the redrawing of the borders of Gaza”, the White House said in a statement.
Appeals from the US to protect civilians followed the resumption of fighting on Friday as a seven-day truce came to an end.
Israel’s prime minister Benjamin Netanyahu said the country’s troops had spent the ceasefire preparing for “absolute victory”.
Speaking at a news conference on Saturday, he said he had instructed the Israel Defence Forces (IDF) to resume the war with “increasing intensity”.
He said 400 Hamas targets had been “eliminated” since the ceasefire ended. He vowed to continue ground operations, saying Israel’s objective of destroying Hamas could not be achieved otherwise.
Strikes have intensified in the south of Gaza, which is now home to most of the strip’s two million citizens.
The Hamas-led Gaza health ministry said at least 193 Palestinians had been killed since Friday, adding to the more
than 15,000 Palestinian dead since the start of the war.
Meanwhile, Palestinian militant groups in Gaza said rockets were fired into southern Israel.
There were no reports of damage or injuries by Saturday night.