The United States believes Saudi Arabia’s flooding of global oil markets compounds the global economic crash at a time of a crisis caused by coronavirus and intends to send a senior official to Riyadh to boost efforts to stabilize energy markets, senior U.S. officials said on Friday. The Energy Department official will work closely with U.S State Department officials and an existing energy attache for months at the least, the officials said on condition of anonymity and on not being quoted directly.