Rating agency Fitch Ratings said on Monday that Britain's exit from the European Union (EU) would have a negative impact on ratings of the EU countries.
"An exit from the EU by the UK ('Brexit') would weigh on the economies of other EU countries and increase political risks in Europe," the agency said.
"Negative actions would become more likely in the medium term if the economic impact were severe or significant political risks materialised," Fitch added.
The agency noted that the economic impact would be lower for the EU than for the U.K.
Fitch also said that there could be risks that Scotland could leave the U.K. or Catalonia could leave Spain.