After more than two decades in exile, U.S. oil companies are being asked by Saudi Arabia to submit proposals to once again help the kingdom with its massive oil reserves, reports The Washington Post.

The invitation was extended by Saudi Crown Prince Abdullah in a private meeting Saturday with executives from seven oil companies.Saudi Arabia, the world's largest petroleum producer, nationalized its oil industry upon the Arab oil embargo in 1973 and has excluded foreign companies from its production operations ever since.