LONDON, June 23 (Reuters) - West African crude oil differentials were under downward pressure on Tuesday, reflecting slow demand in Asia and competition among different grades.

• U.S. President Donald Trump said 19 millions barrels of oil flowed out of the Strait of Hormuz on Monday, and pointed to falling oil prices in a social media post on Tuesday. The Strait was effectively closed by Iran for months due to the U.S.-Iran war.

• In the last known offer level, Exxon offered a cargo of Angolan Hungo with August 6 to 7 loading dates at dated Brent minus $4.05 per barrel on Friday.

• There is potential for differentials to fall further, one trader said.

• Europe is seeing increased offers of crude from outside the region due to poor demand in Asia, which is weighing on differentials, traders said.