UPDATE 17/03/2015: This article has been expanded to include the full statement from South West.
Commuters on a South West Trains service at Basingstoke station were shocked when an announcer told them only thin people were allowed to sit down.
A statement on the train's loudspeaker said: "We are going to be like sardines on this train, so can I ask that only slim people sit on the three seaters. If you are fat then it is simply not going to work."
One passenger told the Daily Mail: "I am not necessarily a big person but most people are larger than those seats anyway.
"It’s pretty disgusting. I would get fired if I said that at my work."
One commenter on the site said: "I was on this train and 90% of people were laughing as it was said in a light hearted manner and actually brightened up an otherwise rubbish morning!"
A spokesperson for South West Trains said: "All passengers are welcome on board our trains. Our guard was aware this particular service was very busy and, in a light-hearted way, pointed out that some middle seat spaces might not be comfortable for passengers with a similar build to herself.
"This was in no way intended as a slight on any customers and the majority of passengers on the train took the comments in the spirit in which they were intended. However, like ourselves, she is very sorry if any passengers were offended by her remarks.
"We run some of the busiest trains in the country and we appreciate that space on some of our trains is limited. To provide extra space and seats for our customers, we are in the process of investing £250m in extra carriages and new trains."