The claim has partial support from authoritative sources. The White House release 'Peace Through Strength: Operation Epic Fury Crushes Iranian Threat as Ceasefire Takes Hold' says 97% of Iran's naval mines had been eliminated and that Iran agreed to reopen the Strait of Hormuz, indicating active U.S. operations against mine threats. Reuters in 'US destroys mine-laying vessels as Trump warns Iran over Strait of Hormuz' and 'Trump says US 'destroyed' mine-laying vessels in Strait of Hormuz; US Navy says escorts not possible - as it happened' reports Trump and U.S. officials describing action against Iranian mine-laying capability in the Strait. However, because the X post itself could not be fetched, I could not directly confirm the exact wording that Trump said the U.S. had 'begun clearing mines,' nor could I verify the separate detail that several U.S. Navy ships were seen crossing the waterway. So the overall substance is supported, but the exact phrasing and all details are not fully verified.