Dimitrov declares that Nigel Farage is "usually very feeble in presenting solid arguments", and suggests that he prefers to "engage in propaganda which deviates markedly from the essence of the debate".
This is all about the Bulgarian and Romanian hordes that are to descend upon us on 1 January 2014, thus provoking UKIP leaflets stating that 29 million Bulgarian and Romanians will have the right to "live, work and draw benefits" in the UK. And, while many will be "fine, hard-working people", the UK may struggle to cope with "another influx" of "people needing jobs, housing schools, hospitals and benefits".
Mr Dimitrov detects an "element of hostility in certain political quarters" over the issue of immigration. But he believes the UKIP's message "… is not the reflection of the prevailing mood of the British people towards the Bulgarian people but it is very disappointing and very discriminatory in certain aspects".
"We react firmly, politely, but very strongly against these assertions and the atmosphere created by this propaganda," Mr Dimitrov goes on to say, asserting that UKIP's pamphlets are "absolutely unacceptable in a European country".
Doubtless, though, the Bulgarian ambassador's intervention will delight Farage and his supporters. Verging very closely on external interference in a domestic election, it will again confirm that foreigners are seeking to influence internal matters which are none of their business.
However, it is rather sad that Mr Farage decided to say that Bulgaria and Romania "do not belong in the European Union", adding that, "these two countries are racked with corruption and organised crime. They should never have been allowed the join the EU since early stage".
One might think that, for those of us who wish to depart from the EU as soon as possible, it is not our place to decide which countries should belong to the EU. It is not so much that Bulgaria and Romania don't belong – being racked with corruption and organised crime has never been a bar to entry, or Italy and Greece could never have joined. The issue, surely, is that Britain does not belong in the EU.
As to potential immigration, supposedly such small numbers of Bulgarians and Romanians areactually looking for work in the UK, that the BBC would have it that you cannot safely estimate real numbers of how many will come. Despite this, the Telegraph translates the percentages into 350,000 people.
It is there that Farage has a really serious problem for, to exclude those potential 350,000 incomers, he must junk the "freedom of movement" and other provisions of the EU treaties. But this would mean accepting the return of upwards of two million Britons currently resident in EU member states.
Not until UKIP can solve that problem can its immigration policy really be considered credible, the lack of which solution suggests that Mr Dimitrov may actually have a point, even if it isn't the one he intended. Seeking to exclude immigrants, while expecting other member states to accept our emigrants, is rather feeble.