CCTV footage has been released appearing to show British Labour leader Jeremy Corbyn walking past empty train seats before he was filmed sitting on the floor complaining about the "completely ram-packed" carriages.
Mr Corbyn was travelling on the three-hour Virgin Trains service from London to Newcastle on 11 August.
A video emerged last week that showed Mr Corbyn sitting on the floor, reading a newspaper, and saying "This is a problem that many passengers face every day" before calling for public ownership of the railways.
But Virgin Trains has released CCTV images that appear to show him and his team walking past empty, unreserved seats before the filming began.
The train operator's footage also shows Mr Corbyn sitting down in an empty seat more than two hours before reaching Newcastle.
A Virgin Trains spokesman said: "We have to take issue with the idea that Mr Corbyn wasn't able to be seated on the service, as this clearly wasn't the case.
"We'd encourage Jeremy to book ahead next time he travels with us - both to reserve a seat and to ensure he gets our lowest fares - and we look forward to welcoming him on board again."
Sir Richard Branson, who co-owns Virgin Trains with Stagecoach, posted a link to the CCTV images on his Twitter account.
Mr Corbyn & team walked past empty unreserved seats then filmed claim train was ‘ram-packed’ https://t.co/R5hawIpQek pic.twitter.com/22t8EkjW5l
— Richard Branson (@richardbranson) August 23, 2016
Mr Corbyn was on his way to debate with Owen Smith in a Labour leadership hustings in Gateshead when the footage was filmed.