No trains will run between Paddington and Reading all day due to power cable damage, Network Rail has announced.
The issue has caused widespread disruption for mourners with some resorting to watching the Queen’s funeral on their phones.
Services run by GWR, Heathrow Express and the Elizabeth line are affected after the fault at Hayes & Harlington.
Network Rail West said: “Due to significant damage to power cables, there are no train services between Paddington & Reading. We expect this disruption to continue for the rest of today. Please check before you travel. We sincerely apologise for the disruption caused on this national day of mourning .
A special 3am service from Penzance to Waterloo put on especially to get mourners into London on time for the funeral got stuck outside Reading.
The sound of the choir at Westminster Abbey echoed through the carriages of delayed trains as mourners watched the service on their smartphones.
Bev Palfreman said she was “absolutely gutted” about missing the start of the funeral.
The 61-year-old from Oakhampton, Devon, said: “The Queen has just been there throughout the whole of my life. This was the only thing I wanted to do.”
Julie Shearsby, a disabled woman who caught the 5.34am train from Bedwyn, Wiltshire hoping to make it to The Mall in time, was stuck for hours on the train that was struck by the falling power lines.
She told The Standard: “We thought that the train had hit something or someone but could hear the cables hitting the roof.
“The driver used the emergency brake and brought us to a controlled halt. I’m feeling exhausted and deflated but we’re still trying to get into central London. We haven’t given up yet.
“I’m disabled so had to wait for the fire service to detrain me.
“The Tube is being held at each station due to points failure at Northfields now. We don’t know where to go as the accessible viewing has closed ages ago on The Mall.”
GWR urged mourners looking to follow the Queen’s journey to Windsor to travel from Waterloo to Windsor & Eton Riverside.
A spokesman said: “We are very sorry for the disruption this morning and are working hard to get services resumed as soon as possible.”
The Elizabeth line is part suspended between Paddington and Reading.
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Rail lines between Reading and Newbury were earlier closed due to a person being hit by a train.
This caused GWR trains to be diverted, delaying more journeys to the capital.
The issues came during one of the UK’s biggest transport operations as mourners descended on London and Windsor.
Around 250 extra train services were planned for Monday.
They included a 3am departure from Penzance, Cornwall, for Paddington, which left with no passengers, according to news website CornwallLive.
The service only ran as far as Reading due to the electric wires damage.
Transport for London recorded 2.08 million Tube journeys on Sunday.
That was up 16% on the same day a week earlier and was slightly above pre-coronavirus levels.
Passengers in London are being urged to delay journeys home due to fears of overcrowding if too many people try to travel immediately after the funeral procession leaves Westminster.