A pregnant mother was left speechless on the London Tube after a fellow passenger allegedly told her to prove she was expecting a baby.

Raayan Zafar, a 32-year-old parent of one, was wearing a "baby on board" badge when she requested to sit in the priority seat, according to the Evening Standard.

Ms Zafar, who is not visibly large yet but suffers from bad morning sickness, was about to sit down when another woman moved to take it and her neighbour challenged her.

She said: "The lady realised I was going for the seat, but the person sitting beside it started arguing with me, saying the lady wanted to sit there and asking 'Why are you taking the seat?'

"I showed him my baby on board badge and he then rudely asked me: 'Where is the baby?'

"I was shocked - is that they way to speak to a pregnant lady? Do I have to carry my maternity notes with me all the time?"

The "baby on board" badge, which was launched in 2005, is supposed to let commuters know a pregnant woman is eligible for a priority seat without an awkward conversation.

Yet Ms Zafar said she does not think people take much notice of the badge.

"People see badges and just ignore them. I think we need to educate people about this," she told the Evening Standard.

"People know about disabled people and they are more considerate because they can see it, whereas with a pregnancy they can't see it at a certain time so they think everything is fine.