(Dmitry Kostyukov — AFP/Getty Images)

The Obama administration on Thursday announced an arms deal with Saudi Arabia valued at nearly $30 billion, an agreement that will send 84 F-15 fighter jets and assorted weaponry to the kingdom.

The administration notified Congress last year of its intent to sell the advanced jets to Saudi Arabia, a key U.S. ally in the Middle East and a strategic bulwark against Iran. The final agreement — which also includes the modernization of 70 existing aircraft as well as munitions, spare parts, training and maintenance — comes at a time of increased tensions in the Persian Gulf.

“This sale will send a strong message to countries in the region that the United States is committed to stability in the Gulf and broader Middle East,” Andrew Shapiro, assistant secretary of state for political-military affairs, told reporters.

Saudi Arabia, which has a predominantly Sunni Muslim population, and Iran, mostly Shiite, have competed for regional influence for decades, and the Obama administration has sought to bolster its security relationship with Riyadh, despite their differences over the response to the Arab Spring.

Tehran, meantime, has increasingly engaged in saber-rattling with Washington. This week, Iran threatened to block the strategically vital Strait of Hormuz if the West imposed an oil embargo. The U.S. Navy’s Fifth Fleet, based in nearby Bahrain, responded by warning against the disruption of vessels’ travel along the route.

“Clearly, one of the threats that [the Saudis] — that they face, as well as other countries in the region — is Iran,” Shapiro said. “But ... this is not solely directed toward Iran. This is directed toward meeting our partner Saudi Arabia’s defense needs.”

The initial notification of the arms sale to Saudi Arabia, in 2010, prompted concern about security implications for Israel. U.S. officials have sought to allay those concerns, and said Thursday that the sale would not degrade Israel’s military advantage.

In announcing the completion of the deal, the White House also touted its domestic benefits, saying in a statement that, according to industry experts, it would “support more than 50,000 American jobs.”

Boeing, which manufactures the F-15, noted that it has a long history with the Saudis, having presented a DC-3 Dakota airplane to King Abdul Aziz ibn Saud, the kingdom’s founder, in 1945.