US Treasury Building.
May not be related to Tariff but likely discussion on status of Treasury Bills hold by China. The last known amount of T Bills hold by China was $760 billion as at end of January 2025. Has China reduce the amount further from Jan to March? The meeting's agenda could be anyone's guess unless it was disclosed by either party.
Technically meeting on T bill is not related to Tariff unless China weaponise it as a response to Tariff war. Remember that the Fed is operating independently from the White House. Fed is not part of Trump's administration and the president has no authority to instruct Fed to fight for his tariff war.
Hong Kong also has about $260 billion of Treasury Bills in its foreign reserves.