Riots in Greece will cost the economy to slow down and will seriously affect the tourism industry with millions of euros in lost business.

Reuters reported; "The riots will have a negative impact on consumer sentiment and retail spending, the market has been frozen for about a week," said Platon Monokroussos, economist at EFG Eurobank.

"All this is creating an atmosphere which is not good for tourism in the long term. Foreign tourists' perception of safety in Greece is definitely affected negatively in a difficult period for tourism due to the global crisis."

A hoteliers are experiencing already several cancellations and it is expected to get worse. Greece's reputation as a peaceful and safe holiday destination is severely tarnished.

The US and other governments are warning their citizens not to travel to Athens and Thessaloniki or to avoid the country all together. Also TripAdvisor has posted the following warning on their site:

"Unrest in Greece - Violent demonstrations continue in several Greek cities after the shooting of a 15-year-old boy by Athens police. The incident ignited long-simmering tension between anarchists and the Greek government. Protests in Athens followed the boy's funeral, and clashes continue in Thessaloniki and other cities. There is also a general strike planned for Wednesday, December 10. This will halt all air traffic from and to Greek airports for that day."

The Athens Mayor Nikitas Kaklamanis has suspended all municipal Christmas events and lighting of central squares and monuments until further notice.