GENEVA, Sept 21 (Reuters) - The United Nations" top refugee official Filippo Grandi said on Tuesday the U.S. mass expulsions of Haitians without screening for their protection needs may contravene international law and constitute forced returns. Grandi, in a statement issued by his Geneva-based agency, urged the United States to lift its Title 42 health-related restrictions in place since March 2020 saying they "deny most people arriving at the southwest U.S. land border any opportunity to request asylum."