A 27-year veteran of Barclays, Weymouth became CIO in February 2000 and embarked on a major reorganisation of the bank's IT departments, outsourcing many previously in-house functions.
Weymouth is taking on the newly created role of Barclays corporate responsibility director. A spokesman for the bank said the scope of the CIO role had reduced since Barclays restructured and created Barclays UK Banking.
Many back-office IT functions became the responsibility of the new business, and the central IT department has cut its headcount from 7,000 to 2,000.
Mike Foley from consultancy group Booze-Allen Hamilton will take over for six months as interim CIO while the bank finds a permanent candidate for the position.