A campaign to halt the closure of Tube ticket offices in London is to be stepped up, with a protest outside Parliament today, ahead of two 48-hour strikes.
Members of the Rail Maritime and Transport union will walk out on February 4 and 11, threatening travel chaos in the capital.
The union will hold a demonstration opposite Parliament, with MPs due to debate the closures, and loss of several hundred jobs, later today.
Labour MP John McDonnell said: "Many MPs are expressing their concern at these drastic cuts in staffing. They know that this will not only undermine the quality of the service, but will also increase the risk to passengers travelling on our network."
Phil Hufton, chief operating officer at London Underground (LU), said: "All Tube stations will remain staffed at all times when services are operating, and we'll be introducing a 24-hour service at weekends during 2015. In future, there will be more staff in ticket halls and on platforms to help customers buy the right ticket and keep them safe and secure.
"We're committed to working with unions and staff to implement changes to station staffing without compulsory redundancies and we've been clear that there'll be a job for everyone at LU who wants to work for us and be flexible. I urge our trade union colleagues to work with us to shape the future of the Tube."
Members of the Transport Salaried Staffs Association (TSSA) will also vote in the coming weeks on whether to launch a campaign of industrial action.