The Department of Health has revealed that the cost of taxis alone jumped from £312,226 to £329,267 over the past year.
A spokesman for the Department of Health said: 'The department ensures that all business travel is made by the most economic means, taking into account any management benefit and the needs of staff with disabilities.'
In a separate answer, the Secretary of State for Wales revealed that the investment in taxis for the department was an estimated £4,000 in 2002.
A spokesman added: 'This figure excludes any amounts spent on taxis, black cabs and licensed hackney carriages outside of departmental contracts and reclaimed by officials as travel and subsistence expenditure. That information could be obtained only at disproportionate cost.'