The Obama administration is poised to announce the sale of nearly $30 billion worth of F-15 fighter jets to Saudi Arabia, U.S. officials said Wednesday. The deal will send 84 new fighter jets and upgrades for 70 more, for a total of $29.4 billion, according to the officials, who requested anonymity because the sale has not been made public. The agreement boosts the military strength of Saudi Arabia, a key U.S. ally in the Middle East, at a time when the Obama administration is looking to counter Iranian threats in the region. Underscoring that effort was a fresh threat this week from Tehran, which warned that it could disrupt traffic through the Strait of Hormuz, a vital Persian Gulf oil transport route, if Washington levies new sanctions targeting Iran\'s crude oil exports. About a year ago, the administration got the go-ahead from Congress for a 10-year, $60 billion arms deal with Saudi Arabia that included F-15s, helicopters and a broad array of missiles, bombs and delivery systems, as well as radar warning systems and night-vision goggles. The plan initially raised concerns from pro-Israeli lawmakers, but U.S. officials reassured Congress that Israel’s military edge would not be undercut by the sale. Additionally, there is now broad agreement among Israel, the Gulf Arab states and the West that Iran poses a significant and unpredictable threat. Saudi Arabia and Iran are bitter regional rivals. Tensions between them were further stoked earlier this year after the U.S. accused Iran of plotting to assassinate the Saudi ambassador to the U.S. in Washington. Saudi Arabia is already the most militarily advanced of the Arab Gulf states, one of the richest countries in the world, and central to American policy in the Middle East. It is also vital to U.S. energy security, with Saudi Arabia ranking as the third-largest source of U.S. oil imports.