A Palestinian official said on Thursday Israel had revised a list of Palestinian prisoners it might release in exchange for a captured Israeli soldier.

The official said the offer had been passed to the Hamas Islamist group, which controls the Gaza Strip, through Egyptian mediators.

Hamas officials said Wednesday that indirect negotiations had been renewed to free Gilad Shalit, an Israeli soldier abducted by Palestinian militants who tunneled into Israel from the Gaza Strip in 2006.

An official in Israeli Prime Minister Ehud Olmert's office, speaking on condition of anonymity, denied however the talks had been renewed, adding that Israel was waiting for a new list to be presented by Hamas.

The Palestinian official said on Thursday: "Israel now said they were ready to release three top Hamas leaders who they had previously refused to free."

He said Israel had also increased the number of Palestinian prisoners it would free on condition they are then expelled from the Palestinian territories.

"We cannot say this is a good offer, there is a big gap between what Israel has offered and what Hamas wants," he said.

In exchange for Shalit, Hamas has demanded the release of 1,400 Palestinian prisoners, including about 450 long-term inmates.

Earlier this month, Olmert rejected the demand to free the 450 long-term prisoners, many of whom have carried out attacks against Israelis.

One Israeli security source has said the Jewish state was objecting to the release of fewer than 50 of the prisoners demanded by Hamas. Israel has about 11,000 Palestinians in its jails.

(Reporting by Nidal al-Mughrabi; writing by Ari Rabinovitch; editing by Andrew Roche)