Delegates travelling to the Cop26 climate summit have been hit with rail chaos after a fallen tree forced the cancellation of services between London and Glasgow.

       Passengers have been told not to travel after a tree fell on overhead electric cables between Rugby and Milton Keynes on the West Coast Main Line.

       Pictures on social media showed the concourse at London Euston station overflowing with hundreds of travellers, stranding those who chose the greener mode of transport to reach the UN environmental conference, which begins today.

       Just before 2pm on Sunday, an announcement in the station revealed all train services had been suspended and the concourse was "exit only" due to overcrowding.

       Avanti West Coast, which runs most services between London and the Scottish city, said disruption was expected on the main line until the end of Sunday.

       “Please DO NOT travel,” the firm said on its website. “Due to an object being caught on the overhead electric wires between Rugby and Milton Keynes Central all lines are blocked.

       “Train services running through these stations may be cancelled or delayed. Customers are advised not to attempt to travel for the remainder of the day.”

       Ticket replacement deals have been arranged with LNER to reach Edinburgh via the East Coast Main Line and with TransPennine Express.

       Multiple scheduled trains have disappeared from departure boards at Euston, leaving thousands of people waiting at the station. Passengers took to social media to report being stuck part-way through their journeys.

       Meanwhile, heavy rainfall and winds elsewhere on the network saw South Western Railway, which operates services in southern England, issue warnings that multiple trees had collapsed onto lines at eight locations. Services will be “severely disrupted” until 5pm on Sunday.

       Tornadoes possible

       Parts of the UK may see tornadoes on Sunday, the Met Office has said, as strong winds and rain batter the country.

       Gusts of over 80mph have been recorded with reports of wind damage which may cause disruption to travel.

       Yellow warnings for wind and rain are in place over large parts of the west and elsewhere, and more are likely.

       Tom Morgan, a meteorologist at the Met Office, said: "We've got a deep Atlantic area of low pressure that's bringing a very heavy band of rain and squalling winds across the whole of the country, but particularly in the south of England.

       "We've seen some very strong gusts of wind on the south coast... and a few reports of damage from the winds. It's not out of the question that there will have been some localised, brief funnel clouds or tornadoes.

       "In the last couple of days we have seen some reports and seen some photos of funnel clouds and water spouts, which are similar to tornadoes."

       Northamptonshire Police said it had received a high number of calls relating to the weather conditions and that trees had fallen on scores of roads in the county.

       A close call was experienced by Reverend Richard Coles, vicar of Finedon, who wrote on Twitter: "We were just praying for the COP26 conference in church when we were hit by what I can only describe as a tornado, which took out a number of trees including this pre Conquest yew."