Sir Terry Morgan has resigned as chairman of HS2 Ltd and Crossrail Ltd, the Department for Transport said.
The announcement was made just days after Sir Terry revealed he expected to be sacked from the HS2 role.
Crossrail – London’s new east-west railway – was due to open this month but its launch has been pushed back until at least autumn next year due to delays in completing infrastructure and testing.
The project’s budget was increased from £14.8 billion to £15.4 billion in July due to “cost pressures”, and in October the Mayor of London was offered £350 million of additional Government funding.
Sir Terry became chairman of HS2 Ltd in August but there has been growing speculation that the high-speed railway will exceed its £55.7 billion budget.