David Powell explains:
I am fairly sure that the USSR plates with an ABT suffix were manufacturers’ plates for an organization called Autoexport who managed the export of Moskvich cars and vans.

FT was the first prefix used in Tunisia after independence from France,in 1956, at which it had to establish a series for foreign residents, including diplomats in the new embassies in Tunis.    In this case, a member of the UN (ONU) had been accorded diplomatic status, to receive this plate.     FT abbreviated ‘Franchise Temporaire’ (Temporary Licence); such vehicles were allowed to enter Tunisia free of local duties, because they were to be re-exported at the end of the owners’ tours of duty. FT is thought to have run from 1956 to sometime in the 1970s.     Blogman knows only of FT 3 and FT 1142 which have been photographed in service.    Anyone else got a picture??  Terry Gray archive

This Triumph Toledo(?) has been to Saint Helena and back(!), and was photographed in Northamptonshire on its Helenan 669 plates.    St. Helena has also been seen with an SH prefix.         The owners were British government officers involved in the administration of the Territory, and their cars were returned at the conclusion of their duty there..

SYR 2480.    Between the 1950s and the 1970s, red plates in Syria were issued to public service vehicles including buses, which is what TG photographed in London in the early 1970s. Serials 2001-12000 were issued to Damascus. Long trip!

16564. One of very few 1960-1970s Somalian plates seen was photographed – also in Northamptonshire -on a Mk 3 Ford Cortina, circa 1974. These were oddly well-made plates for such a backward territory; perhaps they were made for them by an international aid process – possibly Italian, as the former colonial power?      In recent decades, the few Somalian vehicles seen in news broadcasts have generally run without bearing plates, as no registration system exists.     Breakaway Puntland (1998), Galmudug (2006) and Somaliland (1996) have established their own systems (see RPWO).

Somalia mini front plate, a la Italiano.

SD 8016 is from the original Swaziland series running from the 1920s to 1979. This Mk. 1 Ford Cortina was seen near Brackley, England, during the 1960s.

From 1937 to ?, these white on red Swedish plates were issued to vehicles temporarily imported.          Terry Gray saw this Fiat in Europe in the 1970s, carrying a normal Swedish plate of the period underneath.

The unusual sighting of this old Swedish tourist import plate was at a Morris Minor rally in Oxfordshire in June 2013!                  (Brumby archive)

San Marino issued special plates to the city police in different sizes for cars and motorbikes.     A poor shot, unfortunately, but it must be kept for posterity, as so few were issued and ever fewer were photographed….. (Gray archive)

From 1958, while still the Belgian Congo, this Belgium-manufactured (Howoco?) series was introduced.     It continued from 1960 independence under the re-named ‘Rep. of Congo (Leopoldville)’ (oval RCL).      If this were a  Congo Belge (CB)-issue, the T would mean it came from Kasai province, but after 1960, the regional codes became simple serial letters.     Later two letters with three numbers LL-NNN superseded these L-NNNN plates. The provenance of this picture is presently unknown. (Gray archive)

From the 1960s to 1995, Argentina’s first countrywide series was issued, with a letter for the State and a up to 6 numerals.      B 131859 is from Buenos Aires (county).      Somewhat dull, in white on black, but a rare sight outside Argentina.      This Peugeot 404 in an odd colour is probably a car manufactured under licence in (RA), where a different colour range was available.                        (Gray archive 1970 London)

Member pseudonym’d  ‘BlackVolga’  identifies the smart oval plate in red and black on white, CD 442 as for Roumania Diplomatic Corps from 1968 to  1992.      On a BMW 2000 ‘Touring’, a fine-looking car in its day.                (Gray archive)