A rail union is calling for an indefinite suspension of the proposed all-night Tube service, which is due to begin on 12 September.
The Rail, Maritime and Transport union (RMT) described the night Tube as a "vanity project" of Mayor Boris Johnson, claiming it was "fundamentally flawed from top to bottom".
Members of the RMT and three other unions will stage a 24-hour strike from Wednesday evening, which will bring the underground network to a standstill until Friday morning.
Talks aimed at resolving the row ended on Monday and are not due to resume until next week at the earliest. Unions could announce fresh walkouts if the deadlock is not broken.
The RMT said the September 12 start date should be suspended, warning the planned weekend night Tube risked "wrecking" expensive infrastructure, compromising staff and passenger safety and leaving essential safety critical engineering and maintenance works "on the shelf".
General secretary Mick Cash said: "Despite all the bluster from Boris Johnson, Londoners need to be aware that night Tube was rushed and botched from the off, and that is why five weeks before it starts staff are striking because they will not accept that their work/life balance should be wrecked to plug the gaping holes in staffing capacity that should have been dealt with from day one.
"It is a measure of the current shambles that no further talks are planned and staffing posts essential to delivering a safe extension of operating hours are still being axed.
"Millions of weekday commuters, who fork out a fortune in fares, risk seeing their safety compromised and their services reduced to chaos so that a few thousand revellers can be shipped home in the early hours of Saturday and Sunday morning, and experienced tube managers know that.
"We urgently need to get talks convened with tube professionals who understand the reasons behind a crisis which should never have been allowed to get this far."
A spokesperson for the Mayor said: "Despite the fair, sensible and generous offer on the table – which will see no-one working more hours than they do today - the unions have chosen not to put it to their members and to reject it outright.
"The fact is that the night Tube is well supported by Londoners and by businesses across the capital. The Mayor believes that most reasonable people see its introduction as a progressive move for transport in our city.
"He urges the unions to get back round the table and avoid this totally unnecessary strike."
Steve Griffiths, LU's chief operating officer, said: “After listening to the unions, we put forward an extremely fair revised offer, which addresses their concerns over work/life balance and rewards our people for the hard work they do in keeping London working and growing.
"Despite this, the new offer has been rejected outright by the union leadership, again without consulting their members.
"We continue to urge them to put the new offer to their members and not subject Londoners to further unnecessary disruption."