Italy has cleared the way to build the world’s largest suspension bridge linking the Italian mainland with Sicily.

Thousands of people marched in the Sicilian city of Messina on Saturday to protest a government plan to build a bridge that would connect the Italian mainland with Sicily in a massive 13.5-billion-euro ($15.

The Italian government said the bridge would be a security asset, which allows it to categorize the project as a military expense and count it toward its NATO spending commitments.