The government has stripped rail operator Southeastern of its franchise after “a serious breach of good faith”.
Transport Secretary Grant Shapps said more than £25m of historical payments due to the Department for Transport were not paid.
He said the Operator of Last Resort would take over the running of rail services in the south east to protect taxpayers’ interests.
Southeastern said passengers would see no change in day-to-day operations.
Mr Shapps said: “There is clear, compelling and serious evidence that LSER have breached the trust that is absolutely fundamental to the success of our railways. When trust is broken, we will act decisively.
“The decision to take control of services makes unequivocally clear that we will not accept anything less from the private sector than a total commitment to their passengers and absolute transparency with taxpayer support.
“Under the new operator, we will prioritise the punctual, reliable services passengers deserve, rebuild trust in this network, and the delivery of the reforms set out in our Plan for Rail – to build a modern railway that meets the needs of a nation.”