The United States sealed a multibillion arms deal with Saudi Arabia, the White House announced on Saturday, a move that solidifies its decades-long alliance with the world's largest oil exporter just as President Donald Trump begins his maiden trip abroad as leader of the free world.

The agreement, which is worth $350 billion over 10 years and $110 billion that will take effect immediately, was hailed by the White House as "a significant expansion of…[the] security relationship" between the two countries.

Simultaneously, Saudi Arabia is in a broad-based push for economic reform, and as part of that effort signed a flurry of deals with private U.S. companies worth tens of billions of dollars.

Lockheed Martin, one of the world's largest defense contractors whose technology was part of the U.S-Saudi accord, said in a statement that the deal "will directly contribute to [Saudi Arabia's] Vision 2030 by opening the door for thousands of highly skilled jobs in new economic sectors."

The arms package represents an enhancement of Saudi Arabia's military capabilities as tensions flare in the region, with the U.S. viewing the Saudis as a linchpin in efforts to check the global ambitions of Iran. The country, the hub of Islam's most revered sites, but is also a target of radical Islamic extremism.

"This package of defense equipment and services support the long-term security of Saudi Arabia and the Gulf region in the face of Iranian threats, while also bolstering the Kingdom's ability to contribute to counter terrorism operations across the region, reducing the burden on the U.S. military to conduct those operations," the White House said in a statement.

For the Saudis, Trump's visit represents a diplomatic and public relations coup for Mohammed bin Salman, the Kingdom's 31-year old deputy crown prince. The U.S.-Saudi partnership has been fraught with controversy since the Sept. 11 attacks, which culminated last year in a Congressional vote to allow 9/11 families to sue the country for its suspected links to the attackers.

Saudi Arabia is the primary destination for U.S. arms sales, according to the Council on Foreign Relations, with the Kingdom purchasing nearly 10 percent of U.S. exports from 2011 to 2015.

We welcome @POTUS Trump to KSA. Mr. President, your visit will strengthen our strategic cooperation, lead to global security and stability.

The pomp and circumstance of the two-day Saudi visit also gives Trump — who sold himself to voters as an inveterate deal maker — a victory to merchandise abroad, just as his political pressures have intensified at home.

Over the course of the last week, the White House has been overwhelmed by news stemming from an inquiry into the Trump campaign's alleged links to Russia, and the abrupt dismissal of former FBI Director James Comey.