For years Bulgaria has been a source of cheap labour for western Europe. Now the tables have been turned on the Black Sea state, as it finds itself facing an acute shortage of workers and turning to far-reaching measures to make up the shortfall: inviting Vietnamese to fill jobs in manufacturing and construction.

“Bulgaria employed Vietnamese workers under communism and they fitted in well. We would offer jobs on contract terms with temporary residence,” Petar Dimitrov, the economy minister, said in an interview with the Financial Times.