A Foreign Office spokesman said: "The Foreign Secretary has arrived in Israel today to demonstrate the UK's unwavering solidarity with the Israeli people following Hamas's terrorist attacks.
"He will be meeting survivors of the attacks and senior Israeli leaders to outline UK support for Israel's right to defend itself."
Speaking ahead of the visit, the Foreign Secretary made clear that no comparison could be drawn between Israel's military response and the incursion by Hamas terrorists.
He told Sky News on Tuesday: "The truth is that the reason we express our solidarity with the people of Israel is because terrorists took action to murder, to kidnap, and we're now seeing reports that they are threatening to execute people that they have kidnapped.
"The idea that somehow there is an equivalence, there is a kind of a balancing act between the actions of the Israeli government and their self-defence and the actions of Hamas and their terrorists is completely inappropriate."
Speaking to reporters during the visit, he said: "Israel has a right to self defence and a right to regain those people who have been kidnapped [by Hamas terrorists]."
It comes as Rishi Sunak said the UK stood “poised” to help Israel militarily if it asked for assistance.
Downing Street also said the Government was not ruling out evacuating some British citizens from Israel.
Meanwhile, it is understood that 17 UK nationals are either dead or missing, including children. A previous estimate had put the figure at more than 10.
Among those known to have died is Nathanel Young, 20, who was serving in the IDF when he was killed during Hamas's terror attack.
Bernard Cowan, who grew up around Glasgow, also died. Jake Marlowe, 26, who went to the same London school as Young, is believed to be missing, while photographer Danny Darlington is feared dead.
Sunak said his administration "stands ready" to support families with loved ones in Israel.
Speaking to broadcasters during a visit to east Staffordshire, he said: "I know there will be families who are anxious about their loved ones in the region.
"I want to reassure them we're doing everything we can, working very closely with the Israeli authorities to establish what is happening on the ground, provide support to people where it is needed."
