Austria has warned it will send soldiers to close the border with Italy in 24 hours if Rome decides to take the "nuclear option" and grant visas to almost 100,000 migrants stranded in the Mediterranean country. Desperate Italian officials have said they are considering allowing thousands of migrants out of the country and into the rest of Europe, as they struggle to cope with the 10,000 people arriving every day. Austria, which shares a border with Italy via Brenner, an Alpine mountain pass, has reacted to the proposals with fury, saying it would immediately introduce border controls in the region. Yesterday during a border visit, Austria's Interior Minister Wolfgang Sobotka said: "Italy granting humanitarian visas to migrants is unacceptable. In that case, we would immediately introduce controls…