The agency flag is divided diagonally into blue and white quarters, with a central white disc enclosed by a blue ring and bearing a blue U. A salvage-directory account assigns it to Remocaldores Ultragas; the website also shows it crossed with signal flag Zulu. The Argentine headquarters suggestion is qualified.
The agency network served Peru, Chile, Argentina, Ecuador, Uruguay and Brazil. Its members included Buenos Aires’ Agencia Marítima Internacional, founded in 1957; Guayaquil’s Grupo Transoceanica and Transoceanica Cia., the latter founded in 1953; Mercotrade in São Paulo; Trans Total in Lima; and Ultramar Agencia Maritima in Santiago.
Argentine, as stated in the source.
Keep the explicit scope label independent; no alias or company identity is inferred.