NATO funds will not be used to finance the 13.5-billion-euro project to build a bridge across the Strait of Messina connecting Sicily and the Italian mainland, the Transport and Infrastructure Ministry (MIT) said on Wednesday.

The clarification came after United States ambassador to NATO Matthew Whitaker raised the issue of whether European countries would adopt a broad definition of defence-and-security spending to meet the 5% of GDP target.

In an interview with Bloomberg, Whitaker said the 5% should not include spending on "bridges that have no strategic military value".

MIT said this would not be the case.

"The Strait of Messina Bridge is already entirely financed by State resources, and no defence funds are earmarked," it said.