Four Republican senators are promising a showdown with the White House over the ten-year, $38 billion military aid deal signed between the Obama administration and the Netanyahu government earlier this month.

The lawmakers, Lindsey Graham, Kelly Ayotte, John McCain and Ted Cruz, told a news conference Tuesday that they are planning to introduce legislation in the Senate that would overturn a provision of the deal, formally called the Memorandum of Understanding, that prevents Israel from receiving any additional funds beyond those allowed under the agreement, and even requires it to return any added funds granted to it by Congress, Reuters reported.

Prime Minister Benjamin Netanyahu has spent the past week defending the deal in the face of critics on the Israeli center-left. It is not clear how Israel will handle a fight between Congress and the White House over a deal it has already signed.

According to the lawmakers, they are acting to protect Congress’s control over federal spending, which they said was curtailed by the US-Israel aid agreement.

According to Reuters, the senators said they were proposing a bill Tuesday that would enable Israel to receive $1.5 billion in additional military aid, as well as renewing some American sanctions on Iran that were removed in last year’s nuclear deal between Tehran and six world powers.

Senator Lindsey Graham gestures during a press conference with members of his Congressional delegation in Caira, Egypt, on April 3, 2016. (AFP/Mohamed el-Shahed)

Senator Lindsey Graham gestures during a press conference with members of his Congressional delegation in Caira, Egypt, on April 3, 2016. (AFP/Mohamed el-Shahed)

Three other GOP senators, Marco Rubio, Roy Blunt and Mark Kirk, are cosponsors of the new bill.

“This is a very dramatic moment in the US-Israel relationship between Congress and the state of Israel. Congress is not going to sit on the sidelines,” Graham, who holds significant sway over the US foreign aid budget as chairman of a Senate Allocations subcommittee, was quoted as saying.

Last week, Graham used a conference call arranged by the Jewish Institute for National Security Affairs to chastise Israeli leaders for accepting the agreement. Both Hillary Clinton and Donald Trump would have been more generous, he insisted, adding that both Republicans and Democrats in Congress support upping the military aid.

“They left money on the table,” Graham said of Israel.

The Obama administration was trying to “neuter” Congress by undercutting its ability to appropriate money, he charged. “I will not stand for that.”

Graham seemed to draw further support from Sen. Bob Corker, R-Tennessee, chairman of the powerful Senate Foreign Relations Committee, who said in a statement last week that the agreement “sends an important signal about our long-term commitment to Israel,” but the amount of money “is ultimately up to Congress to decide.”

US President Barack Obama, right, and Israeli Prime Minister Benjamin Netanyahu hold a meeting in the Oval Office of the White House in Washington, DC, November 9, 2015. (AFP PHOTO / SAUL LOEB)

US President Barack Obama, right, and Israeli Prime Minister Benjamin Netanyahu hold a meeting in the Oval Office of the White House in Washington, DC, November 9, 2015. (AFP PHOTO / SAUL LOEB)

The agreement was signed last week in Washington after over three years of on-and-off negotiations.

Obama’s national security adviser Susan Rice, who witnessed the signing, called it a signal of Washington’s “unshakable commitment” to the security of the Jewish state. It is the largest such deal ever offered by Washington to a foreign state.

The total includes $33 billion in foreign military financing funds — which is money used to buy materiel and ammunition — as well as $5 billion in missile defense funding. Under the previous arrangement, Congress approved funds for Israeli missile defense systems, including Iron Dome, separately and on an annual basis.

The old agreement, set to expire by the end of 2017 and be replaced by the new one in early 2018, allowed Israel to use 26.3 percent of the aid to buy products from its own domestic defense industry. The new deal phases out that amount over several years, until all US-granted aid is spent on American-made products.

The new agreement also eliminates Israel’s ability to spend a fraction of the funds on fuel for its military.

US National Security Advisor Susan Rice at the signing ceremony of a $38 billion defense aid deal with Israel at the State Department on September 14, 2016 (screen capture: State Department livestream)

US National Security Advisor Susan Rice at the signing ceremony of a $38 billion defense aid deal with Israel at the State Department on September 14, 2016 (screen capture: State Department livestream)

In his comments last week, Graham said lawmakers wanted to give Israel $600 million for missile defense — $100 million more than the agreement proposes to provide in 2019, as well as a $300 million hike in the foreign military financing account.

Republican lawmakers have said that Israel was pressured into signing the agreement out of fear of growing Iranian power in the wake of the nuclear deal and growing Iranian assertiveness throughout the region.