Israel on Tuesday was preparing to release 26 long-serving Palestinian prisoners, the second batch of 104 inmates who are to be freed in line with commitments to US-brokered peace talks.
The release, due to take place late at night, will see 21 prisoners going to their homes in the West Bank.
The remaining five were being driven to a holding area on the Israeli side of the Erez crossing to the Hamas-run Gaza Strip, ahead of their release later, Israel Prisons Service spokeswoman Sivan Weizman told AFP.
All 26 were convicted for killing Israelis, with most of the attacks occurring before the 1993 Oslo Accords, which granted the Palestinians limited self-rule but failed to bring about an independent state.
Although Israel is currently engaged in direct peace talks with the Palestinians -- relaunched in late July after a three-year hiatus -- the move has sparked tensions within Prime Minister Benjamin Netanyahu's coalition.
And Israel has pledged to push through a wave of new settlement tenders in tandem with the release, in a move which officials say was coordinated in advance.
"The decision to release the prisoners is one of the most difficult I've had to make," Netanyahu told his rightwing Likud party on Monday in remarks broadcast on public radio.
"It is unjust because these terrorists are being released before completing their sentence. My heart is with the families of the victims."
Netanyahu agreed to release a total of 104 Palestinian prisoners in stages as part of the resumption of talks aimed at resolving the decades-old conflict.
A first tranche of 26 prisoners was freed on August 13.
Netanyahu spoke by telephone on Monday to US President Barack Obama about the peace talks and wider Middle East issues, a White House statement said, without elaborating.
The talks are held under a US-imposed media blackout but a senior Palestinian official said on Tuesday that Israel had adopted hardline positions and negotiations had so far produced "no tangible progress".
"The current Israeli negotiating position is the worst in more than 20 years," Yasser Abed Rabbo, a top official with the Palestine Liberation Organisation, said in a statement.
"They want security first, and that the borders of the state of Palestine should be set out according to Israeli security needs that never end, and that will undermine the possibility of establishing a sovereign Palestinian state."
'Are we crazy'
The prisoners were taken from other facilities to Ofer prison on Monday, where they spent the night ahead of their release, Weizman said.
She said the West Bank prisoners would be driven from Ofer to the nearby Beitunia crossing from where they would travel to Ramallah.
On Monday evening, around 2,000 Israelis rallied outside Ofer, among them relatives of militants' victims, chanting "Death to terrorists!" and holding placards reading: "Are we crazy? We're releasing murderers."
On Tuesday evening Israel's Supreme Court was hearing a petition by bereaved families against the prisoner release.
Such requests are regularly turned down by the court.
The issue is also sensitive for Palestinians, who generally view those held in Israeli jails as political prisoners punished for resisting occupation.
Nineteen of the 26 due for release are members of the Fatah party led by Palestinian president Mahmud Abbas, three are members of Hamas, and four are from the leftwing Popular Front for the Liberation of Palestine (PFLP), according to a list released Sunday.
Media reports suggest Israel is planning to announce construction of 1,500 new settler homes in the coming days, up to two thirds of them in annexed east Jerusalem.
Last week, an Israeli official said new tenders were to be announced in the large settlement blocs and in east Jerusalem "in the coming months" as part of "understandings" reached with both the Palestinians and Washington.
The Palestinians -- who view continued settlement construction as a major obstacle to peace -- flatly denied any such agreement.
In August, Israel announced plans for more than 2,000 new settler homes in tandem with the first prisoner release, angering the Palestinians.