Train users have been advised to only travel if "absolutely essential" during this week's amber-alert heatwave. The message follows record-breaking temperature predictions at 37C in some parts of Wales - read more about the weather where you are here.
The latest travel warning has come from Network Rail, who has warned of travel disruption across Wales and England due to the weather. A spokesman for the company, Jake Kelly, told BBC Radio 4: "Our advice very strongly to customers in England and Wales today and tomorrow is to only travel if absolutely essential, and to expect a very reduced train service and delays."
Mr Kelly added that service resuming as normal on Wednesday "will depend on the damage that the weather does to the infrastructure." Their warning follows Transport for Wales' announcement that some services would be changing due to the extreme heat - read more about that here.
Read next: Hottest areas of Wales today as country set to see 37C+
Damage limiting measures such as temporary speed restrictions have been in place across the TfW network since Sunday as a result of the high temperatures. Along the east coast mainline in England, Network Rail has had to cancel trains altogether. He said: "Unfortunately, there won't be a train service and passengers should not travel."
However, Mr Kelly explained that this is all new territory for rail companies and they are managing the situation as best as they can. He explained: "We haven't taken any of those decisions lightly, but we've not been faced with these exceptional temperatures before. We're spending hundreds of millions of pounds a year on making the railway more resilient but ultimately faced with weather like we've never faced before, the infrastructure will suffer so we've had to put in place arrangements."
Looking ahead to the rest of the week, Mr Kelly added: "We hope and expect to run a full service on Wednesday and beyond, but that will depend on the damage that the weather does to the infrastructure over the next couple of days. We have lots of plans in place to make sure that we can run."
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