After 15 months of devastating war, Israel and Hamas reached a ceasefire on Wednesday that would halt the conflict in Gaza and ensure the release of the remaining 98 hostages held by militants in the region.

The multi-phase deal, brokered and guaranteed by the United States, Egypt and Qatar, will mark the first ceasefire since a week-long truce in November 2023. The agreement will come into effect on Sunday.

If fully implemented, it would permanently end the war that began with Hamas's attack on the Jewish state on October 7, 2023.

How will the ceasefire begin?

The agreement calls for an initial six-week ceasefire, with both sides halting fighting. The agreement says Israeli troops will begin redeploying eastward from Gaza's urban centers toward what Israel calls a "buffer zone" on the Palestinian side of the border.

Crucially, at the end of the first phase, the deal also requires Israeli forces to leave the Zarim corridor, a key route that separates the northern and southern Gaza Strip, and to leave Gaza's border with Egypt within 50 days.

Under the terms, the Rafah crossing linking Gaza and Egypt, which Israel captured and largely destroyed last May, is expected to reopen. This would restore the strip's only link to the outside world, which before the war was not under direct Israeli control.

Will Palestinians be allowed to go home?

Gaza residents will be allowed to return to their homes, including Palestinians displaced from northern Gaza during the war, estimated to number in the hundreds of thousands.

An Israeli official said Israel insisted on deploying "security arrangements" run by an unnamed private company at checkpoints from south to north. Their goal is to ensure that militants cannot return to northern Gaza, from where Hamas launched most of its October 7, 2023 attack that killed 1,200 people, according to Israeli authorities.

According to international observers, the deal also requires Israel to allow 600 truckloads of humanitarian aid per day into the shattered territory, half of which will be allocated to northern Gaza, where people suffer from severe hunger.

The northern region has been hardest hit by Israel's devastating retaliatory offensive, which has killed more than 46,000 people and reduced much of the strip to rubble, according to health authorities in the Hamas-controlled region.

International aid groups say infrastructure for delivering food, medicine, fuel and other goods to Gaza will need to be significantly expanded as the volumes stipulated in the deal will at least triple the amount entering the Strip.

Which hostages held in Gaza will be released?

For Israel, a key victory in the first phase of the deal is the return of the 33 hostages still held by Hamas, including children, civilian women, female soldiers, people over 50 years old and the wounded.

It's unclear how many people who fit that criteria are still alive, although Israeli officials said this week that "many, most of them" are still alive.

Under the deal, three female hostages will be released on Sunday, followed by at least three more every seven days. Crucially for Israel, the living hostages will be released first, followed by the dead at the end of the six-week period.

What about Palestinian detainees?

Israel has pledged to free 30 Palestinians held in Israeli prisons for every civilian hostage released, a number that would increase to 50 Palestinian detainees for every female Israeli soldier. At this stage, the focus will be on the release of Gazans detained during the war but who were not involved in Hamas's attack on October 7, 2023.

More than 100 Palestinians serving life sentences on murder and terrorism charges will also be released, with some exiled to third countries.

Between 1,000 and 1,650 Palestinians are expected to be released during this phase of the deal, depending on how many hostages are ultimately released alive from Gaza.

Do more details need to be agreed upon?

No later than day 16 of the ceasefire, the parties will begin negotiations on a second, potentially more difficult, phase: the release of the remaining 65 hostages, all men under the age of 50, including soldiers, in exchange for all Israeli hostages from Gaza Withdrawal of troops and permanent ceasefire.

In the second phase, expected to last six weeks, the number of Palestinian prisoners released in exchange for each Israeli soldier is likely to be much higher.

Negotiators also discussed a possible third phase of the deal, which would see the return of Israeli hostages and the bodies of Palestinian militants, with Gaza's reconstruction beginning under the supervision of Qatar, Egypt and the United Nations. However, analysts say a merger between Phase 2 and Phase 3 is increasingly likely.

Will the ceasefire break down?

Israeli Prime Minister Benjamin Netanyahu has repeatedly stated that he is unwilling to end the war completely before achieving "total victory" and completely "destroying" Hamas.

That makes a resumption of fighting after an initial six-week truce highly likely.

However, international pressure - possibly including from incoming US President Donald Trump, who has claimed responsibility for the cease-fire - could force the veteran Israeli leader to leave the country beyond the first phase Continue to implement the ceasefire agreement and completely stop the war.

Mapping and data visualization by Aditi Bhandari