Network Rail bosses have defended lucrative additional bonus pay for executive directors ahead of a key vote.
Members of the not-for-profit firm, who are the equivalent of shareholders, today met in Cardiff for their annual meeting.
As well as deciding whether to re-appoint the current board of directors they will have the option whether to grant five bosses a bumper bonus package worth £2 million.
The payout, which will only come into full effect if "tough" targets are met, comes on top of their six figure salaries and an annual bonuses worth up to £1.2 million.
Unions have attacked the package, likening it to "rewarding failure" in light of rising train fares and punctuality and safety concerns.
But non-executive director and chairman Richard Parry-Jones insisted that Network Rail has had another "solid year" of progress.
He said: "As our annual bonus announcement earlier this year clearly demonstrated, Network Rail senior executives are rewarded only when exceptional performance exceeds tough targets which have been approved by our members through an open and transparent process.
"If targets are not met, or safety compromised, no bonuses are paid."
But the Transport Salaried Staffs Association's (TSSA) general secretary Manuel Cortes said union members were deeply unhappy about the proposal.
He said: "Rail passengers, who have seen fares increase by 16% since the last election, will simply not understand why bosses are rewarding themselves on a first class gravy train, while they are suffering a second class service."
A vote on the payout is expected this afternoon.