Saudi Arabia is shortly expected to award one of the world’s biggest border security contracts, underlining how the global terrorist threat has made homeland security an increasingly lucrative area for defence contractors in recent years.

Raytheon of the US, Finmeccanica of Italy, along with EADS, Europe’s leading aerospace and defence group, and Thales of France are all on the final shortlist for the contract, which is expected to be worth bet­ween $10bn and $15bn.