Talks aimed at resolving a dispute which led to strikes on London Underground were held on Wednesday and will resume later in the week.
Members of the Rail, Maritime and Transport union walked out last week, paralysing Tube services which caused travel chaos for millions of passengers.
The union is seeking a cut in the 35-hour working week of its members.
A Transport for London spokesperson said: “We met with the RMT today and discussed the ways we can further help our colleagues manage fatigue.
“We invited the RMT to meet with us again on Friday and look forward to continuing our discussions.”
