asked the Secretary of State for Defence what is his estimate of the value of United States military, naval and air weapons and equipment, respectively, purchased by the United Kingdom and of the corresponding British weapons and equipment purchased by the United States in the past 10 years.

This information is not available in the precise form requested.The total values of contracts placed for defence equipment of United States manufacture—but excluding subcontracts placed by Ministry of Defence contractors—in the last four years were:

	£million
1971–72	6·3
1972–73	12·8
1973–74	9·1
1974–75	39·5

To differentiate between military, naval and air equipment and to give similar information for earlier years would involve disproportionate time and effort.The United States Government have so far purchased few items of British defence equipment, in terms of complete weapons systems. However, over the last decade, United States purchases have included Harrier aircraft, head-up displays for American military aircraft, aircraft training simulator systems, military aircraft engines, and certain electronics equipment. In total, these sales are estimated to be worth approximately US$600 million. It would be impractical to subdivide this figure between military, naval and air equipments with any accuracy. In addition to the sales covered by this figure there will have been sales of some equipment which it is impossible to segregate from civil business in the trade statistics.