A 24-hour London tube strike is set to go ahead today after talks to avert action failed.
The Rail, Maritime and Transport union (RMT), Transport Salaried Staffs Association (TSSA), and Unite members plan to walk out at 18:30 BST.
RMT general secretary Mick Cash said the "action is on" and "there are no further talks planned at this stage".
The potential strike action is over the introduction of a new night tube service, which is due to start at weekends from mid-September on parts of the Central, Jubilee, Northern, Piccadilly and Victoria lines.
The action will mean there will be no tube services at all from tomorrow evening and all day Thursday.
On Monday London Underground bosses offered a deal which included an average 2 per cent increase on basic pay, and a £500 non-consolidated "launch bonus" to all staff on night Tube lines or at stations serving those lines.
They also offered a £2,000 "transition bonus" for drivers working on the overnight services.
Previously a 0.75% pay increase with an additional payment of £250 for drivers was offered.
London Underground chief operating officer Steve Griffiths said that a "full and final" offer had been made in an attempt to conclude months of talks.
"Many of our staff will not be affected by the new services as we are operating Friday and Saturday night services on five lines. We are also hiring 137 more train operators specifically to work on the night Tube," said Griffiths.
He added: "For those who are affected, it will mean a few extra nights per year within the existing working week.
"No-one is being asked to work more hours than they do now. We are not asking staff to work unlimited nights and weekends."
RMT general secretary Cash said: Despite strenuous efforts by union negotiators to press London Underground to address the issues of fairness, safety, work-life balance and equality at the heart of this dispute, they have come up with nothing in the talks."