TSSA has reached an agreement with London Underground representatives and suspended strikes next week. The transport union representing hundreds of ticket office staff was planning to join members of RMT in a two-day walkout on 6 and 7 February.
TSSA said on 30 January that they will not strike after London Underground offered to create 325 extra posts in an attempt to "pave the way for a resolution to this long-standing dispute".
RMT announced on Friday 27 January that their strike action would still go ahead after talks with conciliation service Acas failed.
Steve Griffiths, London Underground's chief operating officer, said: "We have made a proposal to both unions in order to end this dispute. We will be recruiting at least 650 new station staff this year, of which 325 will be additional new roles."
A spokesperson for TSSA said: "We believe London Underground's latest proposal pave the way for a resolution to this long-standing dispute. We recognise that what is now on the table goes some way towards restoring adequate safety on our Tube for both passengers and staff. Consequently, we will suspend next week's planned strikes."
RMT leader Mick Cash said: "RMT will not stand by while safety is compromised on London Underground off the back of cash-led cuts to staffing levels that the union has warned would have a serious, lasting and corrosive impact for staff and passengers alike. That is why our members are taking this further action."