Italy has announced a ban on large cruise ships sailing into the northern city of Venice. Culture Minister Dario Franceschini said the ban was approved during a Cabinet meeting on July 13 and will take effect August 1. It covers the lagoon near the city’s St. Mark’s Square and the Giudecca Canal. The lagoon area is used by cruise ships stopping in Venice. Venice is built on a system of canals. Franceschini said the government decided to act fast to avoid the U.N. culture agency UNESCO adding Venice to its list of World Heritage in Danger sites at an upcoming meeting in China. UNESCO suggested last month it could put Venice on the list. The agency says the cruise ships -- which carry and unload thousands of day-trippers -- threaten the surrounding water environment.