While immigration overall to the UK dropped to its lowest for the past two years in 2016, the number of Romanians and Bulgarian migrants to Britain reached an all-time high of 74,000 people.
Overall annual net migration to the UK by September 2016 stood at 273 000 people, falling by 49,000 people compared to the same period in 2015, the latest migration data revealed by the Office for National Statistics, ONS, shows.
The first ever figures published after the Brexit vote in June 2016 show that immigration to the UK has fallen below 300,000 people for the first time in two years.
Nicola White, head of international migration statistics at the ONS, pointed out the number of Eastern Europeans who had decided to leave the UK by September 2016 as significant.
A total of 39,000 people from the EU-8: Poland, Slovakia, Latvia, Lithuania, Czech Republic, Hungary and Estonia quit Britain during the observed period, with Poles being the most numerous, 12,000.
At the same time, a record number of Bulgarians and Romanians migrated to Britain in the first nine months of 2016. Their number grew by 19,000 as compared to 2015, reaching 74,000.
''Although we have seen a fall in net migration of EU8 citizens there have been continued increases in immigration from Romania and Bulgaria, so it is too early to say what effect the referendum result has had on long-term international migration'', the statistician said.
Prior to the Brexit vote, a total of 170,000 Romanians and 65,000 Bulgarians were working in the UK.
The total number of nationals of EU member states that migrated to Britain in the first nine months of 2016 dropped to 165,000.
Bulgarians and Romanians gained the same rights to work in the UK as other EU citizens in January 2014 and the numbers working in the UK have grown steadily since then, drawn partly by the low unemployment level of about 5 per cent, the third lowest in the EU.