Fresh talks are taking place today in a late effort to avoid more strike action on the London Underground, planned for this Sunday.
The Rail, Maritime and Transport (RMT) union is meeting with LU bosses at conciliation service Acas.
An RMT spokesperson said yesterday: "RMT has been available for further talks throughout the weekend and we can confirm that those talks will now convene at Acas on Tuesday morning."
More than 3,000 of the union's members are poised to walk out from 6pm on Sunday until 10am on Monday and then again from 10am on Tuesday 7 February until 1am on Wednesday 8 February, with more dates to be announced in March.
It is the latest action in the long-running row over the closure of Tube ticket offices and job losses. A walkout last month over the issue shut down the majority of Zone 1 stations.
That action also involved members from the TSSA, though the TSSA has said it will not be taking part in the latest strikes.
It said LU's newest proposals - involving the creation of additional posts - "pave the way for a resolution" and the union wants further talks with management to clarify the details.
The union's overtime ban remains in place while representatives seek more talks with Tube bosses, though TSSA general secretary Manuel Cortes said the offer "goes some way towards restoring adequate safety on our Tube".
Steve Griffiths, LU'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. We are having further discussions this week to provide clarification on the implementation of these proposals.”