From United Kingdom, visitors can apply for a visa through one of the embassy of Vietnam in United Kingdom below or apply for a Vietnam visa  online. Here below is the specific address of Vietnam Embassy you may concern:

Embassy of Vietnam in London  UK
12-14 Victoria Rd., London W8-5rd, UK
Tel: (4420) 79371912
Fax: (4420) 79376108

Besides, citizens in Argentina can select among 3 options to get visa to Vietnam:

–          Visit Vietnam Embassy in Argentina or in any other countries to get Vietnam visa done there.

–          Apply for Vietnam visa on arrival at https://vietnamvisaonentry.com/apply-online/ and pick up your visa at one of 3 international airports in Vietnam

–          Apply for Vietnam visa code at https://vietnamvisaonentry.com/apply-online/ and get visa stamped at Vietnam Embassy where you wish to pay a visit to.