The US has pressured Israel to ease the Gaza blockade, insisting that Tel Aviv should not link ending the siege to the release of Israeli soldier Gilad Shalit.

According to the Israeli daily Ha'aretz, three weeks ago the US administration sent a diplomatic note to the Israeli Defense Ministry, the Foreign Ministry and the Prime Minister's Office, officially protesting the Israeli policy over keeping the Gaza Strip under siege.

The note, focused Tel Aviv's policy toward the Gaza Strip, was the fruit of discussions between senior US officials, including Secretary of State Hillary Clinton and special Middle East envoy George Mitchell.

The US administration believes that linking the case of Shalit to lifting of the Gaza siege is not a constructive move.

"Until you change this [keeping the Gaza population blockaded and under pressure], it will be impossible to progress," the note read, according to a source quoted by the paper.

"This policy has not led to progress on the Shalit case and we do not think that it is contributing to anything," it said.

Shalit was captured two years ago during a cross-border operation carried out by Palestinian fighters in Gaza.

The note insists that Israel opens the Gaza Strip border-crossings and allow food, cash and medicine into the territory.

The note also focused on construction materials such as cement and iron, which would be used to rebuild the damage caused by Israel's three-week Gaza offensive last winter.

Israel keeps all the crossings into the Gaza Strip closed despite of a humanitarian situation in the region, and conditions the opening of the Gaza crossings to Shalit's release.

However, Hamas - the democratically-elected ruler of Gaza -- has demanded that the release of Shalit be negotiated as part of a separate prisoner exchange.