London is set to grind to a halt again this week as Tube strikes look set to go ahead over a dispute about pay and conditions for the introduction of a 24-hour train service in September.

Unions are expected to reject an offer put on the table by the London Underground on Friday 31 July, meaning a second Tube strike is likely to take place from the evening of Wednesday 5 August. Talks between unions Aslef, RMT and TSSA and London Underground are ongoing.

The strike is due to begin at 6.30pm and take place for 24 hours, leaving commuters queuing for other means of transport around the capital on Thursday 6 August. Although unions do not oppose the 24-hour Tube service, workers are seeking assurance on the number of weekends they would be required to work.

Which services are running?

The DLR, London Overground, tram and Tfl Rail services will be running as normal, but are expected to be busier than normal. Overground and DLR stations with an interchange with the London Underground may be affected.

All other National Rail services will operate as normal. However, on Wednesday afternoon (5 August) and during peak times on Thursday, National Rail services and terminals within London will be much busier than usual.

Are there extra services?

Yes. About 250 extra buses on the roads to help Londoners get around during the strike, with volunteers at bus stations to provide customers with travel information. TfL advises customers to travel outside peak hours on Wednesday afternoon and Thursday.

Coaches on some London routes will run more regularly during the strike. For up to date information on bus services follow @TfLBusAlerts. Follow @TfLTrafficNews for travel information.

Cycle hubs will be restocked more frequently during rush hours on Thursday. Extra river services will be provided on 6 August between central London and Canary Wharf and central London and Putney.

Can I use my ticket?

Printed single Tube tickets will be accepted on bus and tram services on reasonable alternative routes but not on National Rail services. Travelcards will be accepted within the zones purchased as normal.

Day Travelcards bought in advance for travel on Wednesday 5 or Thursday 6 August can be returned before the day of travel for a full refund. Pay as you go fares (on Oyster or contactless cards) will be charged for the services used and will not be refunded.