WASHINGTON — Another bipartisan push is afoot by US lawmakers to bolster funding for Israel's missile defense beyond what is requested by the president in the fiscal 2017 defense budget.

While several influential lawmakers are calling for added funding for such US-Israeli partnership efforts like the Iron Dome air defense system, David's Sling, a medium- and long-range air defense system, and the Arrow family of anti-ballistic missiles, none would say the exact amount being sought.

Yet, Adm. James Syring, Missile Defense Agency director, said during a Senate Armed Services Strategic Forces Subcommittee hearing Wednesday that the request from Capitol Hill for funding on top of the president's request of just under $150 million amounts to a total of "almost $600 million."

Israel traditionally receives significant Ccongressional plus-ups from the administration’s budget request for cooperative missile defense programs. Over the past 10 years, Congress has appropriated $1.9 billion more than was originally requested by successive administrations.

Last year, Congress augmented the administration's request for Arrow and David's Sling programs by more than 100 percent.

The amount anticipated this year is more than what was enacted for Israeli missile defense funding in 2016. The president requested roughly $150 million and Congress enacted $488 million, according to Syring. Israeli missile defense program funding got a boost from Congress in 2015, as well.

Lawmakers seeking a boost for missile defense funding this year said Wednesday that Israeli and US national security are strongly linked and that Israel's missile defense innovations are significant to the US.

"Missile defense is crucially important, and coming out of the Iran deal, we want to make clear our commitment to their security has not wavered," said House Armed Services Ranking Member Adam Smith, D-Wash. "Any threats Israel faces from missiles from the south — from the Gaza Strip, Islamic jihad and Hamas — and from the north and Hezbollah, we want to put them in the position to have a very strong deterrent to that."

Rep. Steve Israel, D-N.Y., a week after a trip to Israel, said Prime Minister Benjamin Netanyahu raised the issue of Iran's ballistic missile technologies in a meeting with US lawmakers. Israel himself was critical of the nuclear agreement between Washington and Tehran for not addressing it.

"One of the reasons I voted against it is it is silent on the issue of Iran's ballistic missile capabilities," Israel said of the agreement. "Iran is exploiting that silence by increasing its testing. That means we now have to increase our defensive technologies for Gulf Cooperation Council countries and others, which means in the long run we will have to increase our investment in Israel."

Israel is a member of the House Appropriations Subcommittee on Defense, which oversees funding to US missile defense programs, as well as the US-Israel collaborative missile defense programs. He said he supports Congress providing continuous funding for such programs.

On the other side of the aisle, Rep. Trent Franks, an Arizona South Carolina Republican who chairs both the Congressional Israel Allies Caucus and the Missile Defense Caucus, called added funding for Israel’s missile defense "essential."

Franks, who is also vice-chair of the HASC's Emerging Threats and Capabilities Subcommittee, said he told HASC Chair Mac Thornberry, R-Texas, of the need and expects to see action in the drafting of the 2017 defense policy bill, and the coming spending bill.

"We have a lot of allies on the appropriations committee," Franks said. "They understand the vital importance of this in terms of our own national security."

A senior member of House Foreign Affairs Committee, Rep. Brad Sherman, D-Calif., said the US can consider its aid for Israel's missile defense a "battle test" of technology the US might use.

"I can't tell you a dollar figure, but there is very strong support for Iron Dome, David's Sling, the Arrow, the whole thing," Sherman said.

Senators probed Syring during two separate hearings on Capitol Hill Wednesday, asking whether he believed the funding the president requested for the Israeli missile defense cooperative program was adequate to ensure Iron Dome has enough interceptors and David's Sling has enough dollars to move it from the development phase and into production.

Syring did not say whether he believed the requested funding would be enough, but he extolled the virtues of the systems produced with Israel.

"There is talk about additional requests from Israel on the Hill beyond that amount which would represent a substantial increase to our president's budget request. I will leave that to you and the committee and the Congress for adjudication and decision," he said during a hearing of the Senate Appropriations Subcommittee on Defense.

"I will testify to the maturity of the program and I am very confident [with what] we did specifically with David's Sling last year and the successes they have had with four successful intercepts late last year," Syring said. "That program is ready for production."

Some of the additional funding provided for Iron Dome, Syring noted, went to the procurement of additional interceptors that were needed after recent conflict.

"I would testify that was absolutely money well spent in terms of what that system did to protect the population," he said.

MDA is in the process of negotiating how the US will deliver funding for the David's Sling production program and for additional interceptors, according to Syring.

The  additional funds directly bolster US industry, Syring noted. The Israeli-US partnership on missile defense — and in particular Iron Dome — includes an agreement for co-production of the system that, in fiscal 2015, brought 55 percent of the work to the US. The US and Israel are also negotiating a similar agreement to produce David's Sling including obtaining the technical data package for the system, he said.

When asked why the president doesn't just provide more funding for Israel up front in the base budget, Syring said, "For me it comes down to how much out of my budget can I afford to budget for Israel development and production ... Everything that I do is risk based analysis on how much funding and what's needed and when and Israel falls into that category."

The Israel Air Force is expected to declare initial operational capability in the coming weeks of the David's Sling Weapon System, a jointly developed program between Rafael Advanced Systems Ltd. and Raytheon Co. to defend against long-range rockets and short-range ballistic missiles; tens of thousands of which are presumed to be in the arsenal of the Iran-backed, Lebanon-based Shiite Hezbollah organization.

Rafael and Raytheon also co-produce Iron Dome.

Barbara Opall-Rome, Israel Defense News bureau chief, contributed to this report. 

Twitter: @JenJudson and @reporterjoe