asked Her Majesty's Government:What is the latest estimate of the cost of the Trident programme, in January 1981 pounds; and whether they will give an analysis of how this amount is distributed over the years 1981–82 to 1989–90.

The cost estimate for a four boat force, at current prices, is some £5 billion spread over 15 years.Up to 1990 inclusive it is considered that a little over £3 billion would be spent.