On Friday, the Senate rushed through a legislation to provide the money for Israel's "Iron Dome" missile system, which is a short-range rocket defense system designed to intercept rockets and artillery shells fired from a range of between four and 70 kilometers.
Republican Senator Lindsey Graham said the Senate vote is a much-needed signal to Tel Aviv that the US is there when Israel needs it.
Efforts in the Senate to approve the money stalled on Thursday after an objection over the cost blocked the bill.
The funding plan must still pass the House of Representatives and be signed by President Barack Obama to become law.
The Senate vote comes two days after the Pentagon announced ammunition deliveries to Israel.
Soon after Israel began its offensive on Gaza, Obama praised the Iron Dome as proof of America's commitment to Israel's security.
Last month, US Defense Secretary Chuck Hagel sent a letter to congressional leadership requesting $225 million in additional US funding for the Iron Dome.
The money would be in addition to the $351 million that’s already under discussion for Iron Dome in fiscal 2015. It would bring total funding to $576 million, compared with the $176 million requested by the Pentagon for the year that begins on October 1.
On July 28, US Senate Majority Leader Harry Reid said that Tel Aviv urgently needs more financial aid from the United States for its offensive against Palestinians in the Gaza Strip.
Israel has been relentlessly pounding the besieged territory for 25 days. More than 1,500 Palestinians have been killed and thousands wounded, including women and children. In retaliation, Palestinian resistance fighters have fired rockets into Israel.
Senate Appropriations Committee Chairwoman Barbara Mikulski last month introduced an emergency spending bill that included funding for the border crisis, Israel’s Iron Dome system and wildfire relief. Republicans have pushed back against the border funding proposal.
In 2013, Congress allocated $235 million for the Iron Dome. And the Obama administration had requested about $176 million for the system for 2015, but the Senate panel doubled the amount.
A Congressional Research Service report in April said that the US had provided more than $700 million to Israel for Iron Dome. The latest bill would lift that to about $1 billion.
Israel already receives billions of dollars of American taxpayers’ money each year. Under an existing 10-year aid agreement between Washington and Tel Aviv signed in 2007, $30 billion of American money is flowing to Israel.
The US annual military aid to Israel has been elevated from $2.4 billion to $3.1 billion through 2017 under the existing agreement.
Meanwhile, US and Israeli officials have discussed a surge in US military aid to Israel in a new aid package that would extend through 2027.