A hashtag showing support for Muslim Australians has taken off on social media following a siege at the Lindt cafe in Sydney on Monday.

#illridewithyou is trending worldwide on Twitter, rising by hundreds of tweets per minute since it began Monday morning.

702 ABC Sydney have had calls from Muslim listeners who say they are too scared to ride on public transport at the moment.

The hashtag appears to have come from a Facebook post from a woman who was riding on a train in Sydney, who noticed a Muslim woman quietly take off her head covering.

The woman said: “No, if you want to wear it, then wear it. I’ll walk with you.”

Another woman took to Twitter and wrote: “If you reg take the bus b/w Coogee/Martin PL, wear religious attire, &don’t feel safe alone: I’ll ride withyou. @me for schedule.”

The woman, Twitter user @sirtessa, then suggested “maybe start a hashtag? What’s in #illridewithyou?”

The hashtag has been picked up by a number of prominant tweeters as well as throngs of everyday users, making it one of the most prominant topics on Twitter.

Take a look at some of the tweets.