UN leader Ban Ki-moon was to enter the Hamas-run Gaza Strip Thursday, hours after a barrage of eight rockets was fired from the Palestinian territory into southern Israel.
The visit comes a day after the UN chief urged Israel's Prime Minister Benjamin Netanyahu to ease his country's restrictions on the coastal territory.
UN security decided to go ahead with the trip despite the rocket attacks, which often prompt Israel to respond to with air strikes on suspected militant strongholds in Gaza.
Ban's schedule is expected to include stops at a school and a Japanese-funded housing project, both in Khan Yunis in the centre of the Gaza Strip.
He is not scheduled to meet with any member of the Hamas-run government.
Ban's visit to Israel and the Palestinian territories comes as he tries to kickstart preliminary talks sponsored by the peacemaking Quartet in a bid to get the parties back to direct negotiations.
On Wednesday, he met with Netanyahu in Jerusalem, and urged Israel to offer "goodwill gestures" to the Palestinians.
Signup to our newsletter and follow us on Facebook and Twitter!
He also condemned rocket attacks from Gaza as "unacceptable" and said he had discussed the delicate informal truce between Israel and militants in the territory.
"I shared with him my concerns about the fragility of the calm and stressed that continued rocket attacks out of Gaza must stop," Ban said, adding that he remained concerned about Israel's restrictions on the territory.
Israel closely limits imports and exports from Gaza, citing security concerns and the need to deny Hamas, which it considers a terrorist organisation, access to weapons and money.
But much of the international community has said the restrictions negatively affects Gaza's entire population, unfairly affecting civilians.
"Gaza remains a priority for me and the United Nations family," Ban said on Wednesday.
"I thus urged the prime minister to take further steps to facilitate the delivery of the United Nations' important humanitarian and development assistance in the service of the Gazan people."
Netanyahu did not directly mention Gaza at the press conference but stressed that Israelis must be protected from "terror".
Ban heads back to New York on Thursday night at the end of a three-day mission to prod Israelis and Palestinians back into direct negotiations on hold since September 2010.