To ask the Secretary of State for Defence (1) what is the United Kingdom Government's current approach to the seismic verification of treaties constraining nuclear testing;(2) if he will outline the important verification difficulties that remain to be resolved before an agreement can be reached by the United Kingdom Government on a comprehensive nuclear test ban treaty.

I refer the hon. Member to the reply given by my hon. and learned Friend the Member for Putney (Mr. Mellor) on 27 June 1988 at column 61, and to the working paper on seismic monitoring tabled in the conference on disarmament in 1985 (CD 610), a copy of which is in the Library of the House.

To ask the Secretary of State for Defence how many scientific personnel are currently employed by

The Ministry of Defence's research establishment at Blacknest, near Aldermaston, employs 27 scientific personnel, including a number of contract staff, who undertake seismological research which could be used in establishing the requirements of a verification regime for further constraints on nuclear testing.

To ask the Secretary of State for Defence what was the United Kingdom Government's annual expenditure, for each year since May 1979, on verification of a global comprehensive test ban treaty.

Information on the costs of seismological research undertaken at Blacknest, near Aldermaston, dating back to 1979 could be provided only at disproportionate cost. I refer the hon. Member to the reply I gave him on 19 October 1989 at column 251 concerning the costs of this work for the financial year 1988–89.