Davis, the shadow deputy prime minister, said the way Kinnock handled the whistleblower, 'an employee who wanted to improve the Commission's financial management' raised serious concerns about his commitment to reform and to an open and honest government.

Andreasen was suspended last week after she claimed the EC's £63bn budget was 'out of control'. A decision has yet to be taken on whether she will be dismissed.

Last week famed EC whistleblower Paul van Buitenen resigned due to disillusionment with financial reforms at the European Commission and his disapproval at the treatment of Andreasen.