Network Rail's chief negotiator Tim Shoveller warns that disruption caused by upcoming strikes will be "significant" for passengers.On Thursday and Saturday, only around a fifth of normal services will run, and half of lines will be closed.Trains will only operate between 7.30am and 6.30pm on both strike days and will start later than normal on the following mornings.

Network Rail's chief negotiator Tim Shoveller warns that disruption caused by upcoming strikes will be "significant" for passengers.On Thursday and Saturday, only around a fifth of normal services will run, and half of lines will be closed.Trains will only operate between 7.30am and 6.30pm on both strike days and will start later than normal on the following mornings.