A Tube strike which had been expected to go ahead on the District line this week has been suspended.
The walkout, which was set for Wednesday, had been organised by the Aslef union in a row about a driver who was redistributed following safety incidents.
TfL said on its website on Monday that the strike would no longer go ahead.
A separate 24-hour walkout on the Jubilee line is still expected take place throughout Wednesday.
Faces of frustration: Battling the Tube strike
That dispute concerns both the Aslef and Rail, Maritime and Transport (RMT) unions.
A second strike on the Jubilee line has also been planned for next Thursday, June 14.
The RMT said it was “bitterly disappointed” that the talks had not resolved the issue and said it made every effort to try and reach agreement with Transport for London.
Staff will walk out in a row over a new timetable.
Aslef said new timetables would increase the number of Saturdays drivers have to work, breaking a previous arrangement agreed by the company and unions in 2015.
A TfL spokesman said: “Our position has remained the same throughout this unnecessary dispute and strike action.
"We are committed to running a safe and reliable railway and to treating our staff in a fair and consistent way. We are satisfied that both of these commitments were met in this case and we are pleased that our customers will no longer be disrupted by further strike action on the District line.”
RMT general secretary Mick Cash said: "RMT is bitterly disappointed that Tube managers have knocked back an opportunity to negotiate a settlement to this dispute in extensive talks that broke up on Friday. They failed to put a single proposal forward.
"It is outrageous that Tube managers are trying to bulldoze through timetable changes without agreement that ride roughshod over existing rostering agreements.
"Drivers are angry at the impact on work-life balance and rightly see this move as the thin end of a very long wedge that could see processes and agreements unilaterally shredded by Tube bosses."
