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

Italy's decision to approve the construction between Sicily and the mainland of what would be the world's longest single-span bridge has set the stage for a legal battle that could further delay a project first conceived by the ancient Romans.

Italy this week approved a US$15.8 billion bridge linking Sicily to the mainland, amid concerns over its scale, seismic risks and environmental impact.