The top US diplomat has faced fierce opposition from both sides to any compromise on mostly irreconcilable demands since he kick-started direct negotiations in July after a three-year hiatus.

Kerry's 10th tour to the region since he took office last March comes as Palestinian and Israeli leaders accuse each other of lacking serious commitment to achieve a lasting peace after decades of conflict.

A State Department official told AFP ahead of the four-day trip that Kerry aims to hammer out a framework to guide the sides through the tough final months of talks, due to end in late April after an agreed nine-month negotiating period.

Kerry and his team, led by special envoy and former ambassador Martin Indyk, hope to have the framework in place soon, addressing the core issues.

These include the contours of the borders of a future Palestinian state, the fate of Jerusalem which is claimed by both sides as their capital, and Palestinian refugees.

The Palestinians want borders based on the 1967 lines that existed before the Six-Day War, when Israel captured the West Bank and east Jerusalem.

But Israel wants to hold onto all of the settlements it has built inside occupied Palestinian territory since then.

On security, Israel wants to maintain a military presence in the Jordan Valley, where the West Bank borders Jordan, under any future peace deal.

The Palestinians reject this demand, seeking instead for an international force to be stationed there to guarantee security.

Kerry's visit comes two days after Israel freed the third of four batches of 104 veteran Palestinian prisoners as a goodwill gesture agreed under the talks process.

However, the release was expected to be followed by announcements of further Israeli settlement expansion on Palestinian territory, an issue that has crippled the talks and angered the international community.

A US State Department official told AFP before the visit that Israel's settlement expansion had created difficulties in the negotiations, and reiterated Washington's position that the settlements are illegitimate.

Israeli media reported Thursday that Netanyahu would postpone the expected announcement of some 1,400 new settler homes until after Kerry's departure on Sunday.

This would be in contrast with previous announcements which directly coincided with the first and second Palestinian prisoner releases.

Several thousand new settler homes, the building of which is illegal under international law, have been announced since the talks started.

Israeli daily Yediot Aharonot said Thursday Netanyahu had come under pressure from the United States and Europe to delay the expected settlement announcement.

"The Americans and the Europeans asked him to postpone the announcement due to concern that the Palestinians would derail the negotiations. The Europeans even threatened that in such a situation, the blame for derailing the talks would be cast solely on Israel," it said.

The Palestinians have threatened to sue Israel through the international courts should it continue to expand its settlements.

But Palestinian president Mahmud Abbas has reiterated a commitment to seeing out the nine months of talks before taking such action.

Despite the differences between the two sides, the 70-year-old former senator Kerry has proved persistent in his efforts to keep the peace process alive.

Source: AFP