Irish Rail says it's putting out enough trains to cope with passenger demand in "the vast majority of cases" after being criticised for a lack of social distancing on train services.

Earlier model Holly Carpenter shared a picture of a group of teenagers sitting together on a corridor floor on the five-past-three Galway-to-Dublin train today.

She said "every carriage corridor looks like this".

Irish Rail spokesperson Barry Kenny says passengers are allowed stand on long-distance trains -- but they're supposed to spread out down the carriage.