JUDITH Chaplin, 53, Conservative MP for Newbury, and an adviser of

John Major, died yesterday.

The Prime Minister said: ''Judith was a dear friend and a trusted

adviser. She had settled into her job, into the House with great aplomb

and would have had a wonderful career there. Norma and I will miss her

very much.''

She is the first MP to die in the new Parliament and her death creates

a by-election in Newbury, where she secured a 12,357 majority at the

General Election.

Mrs Chaplin died at St Mary's Hospital, Paddington, west London, from

what are understood to be complications arising from a blood clot. She

had surgery on Wednesday at the hospital.

She had worked closely alongside Mr Major for some years and appeared

likely to become one of the first back benchers of the new intake to be

given a ministerial post.

She had been Mr Major's political secretary since 1990 and before that

was his special adviser when he was Chancellor of the Exchequer.

She was head of the policy unit of the Institute of Directors from

1986 to 1988.

Mrs Chaplin was educated at Wycombe Abbey and Girton College,

Cambridge. She first worked in advertising and then founded and ran an

independent school for young children in Norfolk from 1967 to 1974.

Sir Norman Fowler, chairman of the Conservative Party, said: ''Judith

was one of the outstanding new MPs and would certainly have become a

Minister.''

She is survived by her husband and four children.