At this point, a diversion from internal mail, to consider foreign mail. Initially internal rates in all the ex-USSR republics applied equally to all other republics, with variations in mail to and from the Baltic states of Estonia, Latvia and Lithuania.
As political policies evolved, so three rates were established: internal, to other CIS (Commonwealth of Independent States) countries, and to the rest of the world, including the Baltic states. I have little evidence from mail in the middle category but I have a few examples of the third category, into which GB falls.
In the USSR the basic world airmail rate was 50 kopecks, but this was quickly raised to more economic levels.
The first example 20 is a surcharge of 450 kopecks, to make a 5r rate (used at Minsk 5.1.93). I have two 5r covers to the UK from February 1992, bearing only USSR stamps.
The lowest rate I have seen with Belarus stamps is 25 roubles. (20 has 4 x 5r stamps on the reverse of the cover.)
21 & 22 are the horizontal and vertical 25r overprints (replacing the 50k value), both also used at Minsk (Jan/Feb 93).
Finally, 23 the first use of the boxed 'TP' [=Taxe Percue = Postage Paid] mark with value in manuscript, here for 24r50 to make the 25r rate, used in Brest 21.1.93. [Two covers, one to GB and the other to Latvia, indicate a surface rate of 15 roubles.] 20.21.22.23.
By the end of December 1992 Belarus had issued 15 stamps (including, in November 92, 3 definitives with scarecely worthwhile values - 30, 45 & 50k (see above) and a miniature sheet, but the highest value stamp was 5 roubles. On 4 January 1993, the second phase of definitives was issued, with values of 1, 2, 3 & 10 roubles.
By coincidence the cover shown below was posted in Slonim on 4 January, and has 5 x 5rouble stamps CUT from the perforated miniature sheet, also shown.
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