The US and Israel signed a bilateral deal on Friday to help curb arms smuggling to Gaza as part of an effort to secure a ceasefire between Israel and Hamas militants.
US Secretary of State Condoleezza Rice said the memorandum of understanding would improve information sharing between the two countries to prevent the weapons from reaching Hamas in Gaza, one of Israel's chief goals in its three-week incursion into the Gaza Strip.
The deal "should be thought of as one of the elements of trying to help bring into being a durable ceasefire ... that can actually hold," Rice said in Washington, adding she hoped a truce would be reached "very, very soon."
Israeli Foreign Minister Tzipi Livni, who was in Washington to sign the agreement, called it a "historic" deal that was a "vital component for the cessation of hostilities."
Only through a "united effort" to combat terrorism could a ceasefire between the two sides be achieved, Livni said.
Israel launched its Gaza offensive December 27 in a bid to curb near-daily rocket and mortar attacks from the strip at its south. More than 1,100 Palestinians have been killed in the offensive. Thirteen Israelis have also been killed, including three civilians.