The new PM refused to guarantee that British steel would be used in the construction process for Trident renewal.
Asked if UK steel would be used, Mrs May said: “The Government has been looking at the Government procurement arrangements in relation to steel, and obviously where British steel is good value we would want to see that being used.”
The PM said a review of alternatives into Trident has found that “no alternative system is as capable, resilient or as cost effective as a Trident-based deterrent”.
May added submarines are less vulnerable to attacks than aircraft and ships and can maintain “continuous, round-the-clock cover”.
Mrs May went on: “Furthermore, we do not believe that submarines will rendered obsolete by unmanned underwater vehicles or cyber techniques, as some have suggested.”
And she stressed that all four nuclear submarines are necessary to keep Britain safe.
She said: “I will not seek false economies with the security of the nation, and I’m not prepared to settle for something that does not do the job.”