Amnesty International called for an arms embargo to stem the tide of blood in the Gaza Strip, urging the United States to scrap plans to ship consignments of weapons to its ally Israel.

"The last thing that is needed now is more weapons and munitions in the region, which is awash with arms that are being used in a manner which contravenes international law and is having a devastating effect on the civilian population in Gaza," said Amnesty regional director Malcolm Smart.

The London-based human rights group said in a statement that the UN Security Council should impose "an immediate, comprehensive arms embargo on all parties to the conflict in Gaza" where more than 1,000 Palestinians have been killed since Israel launched a massive offensive on December 27.

The US military announced on Tuesday that it had cancelled a planned shipment of munitions from a Greek port to a US warehouse in Israel due to objections from Athens.

Amnesty said another ship carrying high explosives and other munitions which left the US a week before the conflict began was also destined for the Israeli port of Ashdod, although its plans to transit via Greece may have altered.

"The US government should not proceed with these or any other arms shipments to Israel, and the Greek and other governments should not allow their ports or other facilities to be used to ferry arms to Israel or the other parties to this conflict," said Smart.

Amnesty also said it is vital that the smuggling of weapons and rockets from Egypt into Gaza is ended, one of the main aims of the Israeli offensive.

"Rockets and rocket-making equipment smuggled into Gaza from Egypt are being used against the civilian population in southern Israel," said Smart.

"A Security Council arms embargo is needed primarily to prevent new weapons supplies reaching the two sides, but it could also send a powerful signal to Israel and Hamas about the Council's determination to uphold international law."