In an internal memorandum obtained by The Independent he warns staff there will be "zero tolerance" of corruption and threatens staff unions that any resistance to his planned shake-up will lead to "turmoil".
The blunt message from Mr Kinnock, who is due to take up his new post as vice-president with responsibility for reform next week, heralds a clash with the unions, which have retained a strong grip on Brussels despite previous waves of reform.
When leader of the Labour Party Mr Kinnock conducted a series of reform battles, both with union leaders and with the hard-left Militant bloc in the party. Observers in Brussels believe his new job poses an even more formidable task. Erkki Liikanen, a commissioner due to return to Brussels, has cast doubt on prospects for change.
Mr Kinnock's letter, drafted on the day of his grilling by members of the European Parliament, spells out the scale of the task that confronts the incoming Commission, led by Romano Prodi, in its promised clean-up. Earlier attempts to change the culture of the bureaucracy have gone wrong, Mr Kinnock argues in his letter, with "vital energy used on turf battles and other disputes rather than on fulfilling the purposes of reform".
The incoming vice-president argues: "The European institutions have, in the public eye, increasingly become associated with impropriety and sleaze. Although many recognise that this perception is an unfair generalisation, the problem exists. Morale, as well as the European project itself, will suffer if we fail to address it.
"Zero tolerance for corrupt activities... is the only acceptable attitude for any public administration, including ours."
Mr Kinnock is due to draw up a detailed blueprint for reform by February, but his comments indicate a tough line on staffing issues.
At his hearing before the parliament this week, Mr Kinnock went further than any of his predecessors in promising a purge of the incompetent and over-promoted.Reuse content