The National Heart and Lung Institute in London has voted to merge with Imperial College on August 1.
It will be followed in 1998 by the Royal Postgraduate Medical School and Charing Cross and Westminster Medical School, a decade after St Mary's Hospital Medical School merged with Imperial.
Virginia Bottomley, Secretary of State for Health, has pledged in principle "a substantial capital contribution" towards a new building for the school.
Imperial's rector, Sir Ronald Oxburgh, said the college was delighted to have its medical school enhanced by an institute of the quality and reputation of the NHLI in partnership with the Royal Brompton Hospital."
* The merger between Queen Mary and Westfield College and the Royal London and St Bartholomew's Hospitals medical schools has cleared another hurdle with the dismissal of two petitions against its private Bill, currently going through the Commons. One was from two Bart's graduates in Norfolk.
Graham Zellick, principal of QMW, said the new faculty of clinical medicine would offer greater curriculum choice.