Israel will not fully reopen its border crossings into the Gaza Strip until Palestinian militants release abducted Israeli soldier Gilad Shalit, the country's security cabinet said Wednesday.

Outgoing Israeli Prime Minister Ehud Olmert convened his cabinet Wednesday to discuss a proposal that would release roughly 1,400 Palestinian prisoners in exchange for Shalit.

After more than four hours, the cabinet emerged to say "it would be inconceivable" to accept an Egyptian-proposed ceasefire deal that calls for Israel to allow items other than humanitarian aid into Gaza without Shalit's release.

Border crossings have been temporarily opened throughout and after the recent 22-day conflict with Hamas to allow humanitarian supplies inside, but items such as building materials are needed to help with Gaza's reconstruction.

"The crossings are open and will remain open to humanitarian aid," said Olmert's spokesman, Mark Regev, according to Israeli newspaper Haaretz.

"Any further widening will be dependent first on the release of Gilad Shalit."

Shalit was taken by Hamas-linked Palestinian militants in June 2006 near the border with Gaza. Two Israeli soldiers were killed during the raid.

Hamas spokesman Fawzi Barhoum refused to link the proposed ceasefire with Shalit's release, said Reuters.

The conflict between Israel and Hamas in late 2008 and early 2009 killed about 1,300 Palestinians, say Palestinian officials. Israeli officials say 13 Israelis, including four soldiers, were killed.

The offensive damaged buildings and infrastructure in the small coastal strip that's home to about 1.5 million people.

Before the cabinet met on Wednesday, Israeli warplanes fired on smuggling tunnels running beneath the Israel-Gaza border, said Reuters.

The attack came after mortar bombs were fired into Israel from the Gaza Strip on Tuesday.

With files from the Associated Press