Pro-EU protesters demonstrate against Brexit with flags outside the House of Parliament on November 13, 2018 in London, England.

The former prime minister of Italy has told CNBC he fears for stability in Europe, and Italy in particular, should there be a chaotic outcome to Brexit negotiations.

U.K. Prime Minister, Theresa May, outlined her draft deal to take Britain and Northern Ireland out of the European Union (EU) on Wednesday evening to her most senior colleagues. The proposal has triggered four resignations from her government, most notably Dominic Raab, the minister in charge of negotiating Brexit.

Speaking to CNBC Thursday, the former Prime Minister of Italy, Enrico Letta, said an unruly departure by the U.K. from the EU could roil European markets and further destabilize his own country.

"There is a link, because the Italian situation is a very unstable one, a very complicated one," Letta said before adding, "Frankly speaking I am scared of an unstable storm, a complicated situation from abroad that can bring instability to the markets and then to Italy too."