By Zachary Cohen CNN

WASHINGTON (CNN) -- President Donald Trump's son-in-law and utility diplomat, Jared Kushner, shocked a high-level Saudi delegation earlier this month when he personally called Lockheed Martin CEO Marillyn Hewson and asked if she would cut the price of a sophisticated missile detection system, according to a source with knowledge of the call.

Pressured to finalize a massive $100-plus billion arms deal in the two weeks leading up to Trump's trip to Saudi Arabia, Kushner hoped to maneuver a discount on Lockheed's Terminal High Altitude Area Defense (THAAD) system during the Saudis' visit to the White House on May 1 -- a request that Hewson said she would look into at the time.

The New York Times first reported the exchange between Kushner and Hewson. CNN has reached out to the White House for comment.

Ultimately, the two sides were able to reach an agreement on a weapons package that amounts to $110 billion in tanks, fighter jets, combat ships and the THAAD missile defense system, according to the White House.

It is unclear how much the Saudis will be paying for THAAD but Trump called it a "billion-dollar system" last month when the US deployed the advanced missile defense radar to South Korea.

Trump is expected to officially unveil the deal when he arrives in Saudi Arabia on Saturday -- the first stop in his 10-day trip to the Middle East. Kushner and several of Trump's other top advisers will also make the trip.

While calling the head of a major defense company and simply asking for a lower price is widely considered an unorthodox negotiation tactic, Kushner's hands-on approach has drawn comparisons to when then-President-elect Trump criticized the stealthy F-35 fighter jet for being too expensive and Hewson gave her "personal commitment" to cut the cost of the program in February.

And the details of how the call took place also provide a window into Kushner's role during negotiations with the Saudis and the range of his influence on matters of foreign policy as a whole.

During last year's presidential campaign and later during the transition, Kushner was identified by Trump's team as the principal point of contact for foreign governments looking to either congratulate the new US leader or begin diplomatic talks.

The 36-year-old commercial real estate magnate started building a relationship with members of the Saudi royal family shortly after the election, a source told CNN, and was on hand when Trump hosted the deputy crown prince, Mohammed bin Salman, in March.

Issues of foreign diplomacy evolved into an interagency effort once the administration began, according to a source, and Kushner's role in negotiating the arms deal was just one part of an larger effort that included the State Department, Department of Defense and National Security Council.

But the scope of Kushner's influence on matters of foreign policy have remained in the spotlight through the early months of Trump's presidency.

CNN reported last month that multiple White House and administration officials said Kushner had eclipsed nearly all of Trump's West Wing and Cabinet advisers in terms of influence and established himself as the key envoy for those outside the administration.

White House press secretary Sean Spicer said at the time that Kushner was working jointly with the State Department to manage the administration's foreign affairs.

"He's continuing to work with them and facilitate an outcome. But he brings a perspective to this, and began doing that during the transition. But again, it's not a binary choice where he's doing this at the expense of somebody else."

CNN's Betsy Klein and Elise Labott contributed to this report.

TM & © 2017 Cable News Network, Inc., a Time Warner Company. All rights reserved.