Tube workers have lifted their threat of industrial action after union leaders said they won a "significant victory" in a dispute over pensions.
The union said the proposals would dramatically affect pensions
Rail Maritime and Transport Union (RMT) members had voted to strike over changes to ill-health pensions.
But the union's general secretary, Bob Crow, said his members had now received the guarantees they were seeking.
Transport for London (TfL) had said the ballot "served no purpose" as no decision on the pension had been made.
"We have now received the guarantees we were seeking that no attempt will be made to introduce cost-cutting changes that would deprive most people who leave work through ill-health of their pensions," said Mr Crow.
"We still believe that the fund rule that allows annual review of ill-health pensions should be scrapped, but we now have written confirmation that it will remain suspended."
A statement from TfL said: "We welcome the fact that the RMT seems to have recognised that there was no basis for industrial action on the issue of pensions.
"The Mayor and Transport for London have put enormous resources into guaranteeing pension levels for TfL employees."
The TfL statement added: "There had been no decision to change pension entitlements and so the RMT ballot for industrial action on a non-issue served no purpose and achieved nothing at all."