What is the ‘Mother of All Bombs’ US could use in Iran?

▲ Escalating

US pulls diplomats from Saudi Arabia as Iran warns it will not back down

On Saturday the US ordered diplomats and other federal employees to leave Saudi Arabia and began drawing down staff at other regional missions, with officials saying Iran is in advanced stages of planning attacks on Americans. A US intelligence memo reportedly makes the same warning. Iranian officials say Iran will not let US warships approach, while Trump is reported to be weighing new attacks. On Thursday Iran said seven tankers were struck in the Strait of Hormuz, and Brent crude hit $112 a barrel.

• Iran's IRGC says it hit four vessels in the northern Gulf and that three more struck mines; Saudi Arabia intercepted drones.
• A person briefed on war planning told NPR the US and Israel are preparing a possible attack on Iran after the US midterm elections; Iran said it is prepared.
• Ministers from Europe and the Middle East meeting in Istanbul urged US-Iran diplomacy and warned against new attacks.
• An oil spill from a tanker strike has reached UAE beaches, and analysts say global emergency oil stocks are at multidecade lows.