The row began when Swedish Foreign Minister Carl Bildt gave a speech to the UN Human Rights Council earlier this month, in which he criticized Cuba's human rights record.
Rodolfo Reyes Rodriguez, Cuba's delegate to the Human Rights Council, is quoted as having said that "Cuba, unlike Sweden, does not persecute migrants or carry out ethnic cleansing that only allows those whose skin and hair color fit with the racial patterns of former Viking conquerors to remain in the country."
Carl Bildt, speaking to the Swedish news agency TT on Wednesday, issued a condemnation of Rodriguez' comments and accused the Cuban delegate of "using unacceptable language."
The foreign ministry called in Cuba's ambassador in Stockholm to explain the comments and apologize on his country's behalf. Some time later the foreign ministry discovered that its diplomatic post had been opened by the Cubans. This too Bildt described as entirely unacceptable.
Bildt conceded that the situation was now so serious that it could be designated a diplomatic crisis.
Rodolfo Reyes Rodriguez has accused Bildt of hypocrisy after the foreign minister failed to mention the Guantanamo base in Cuba or the American-led war in Iraq during his speech on human rights.