Social media rages after 'Vote No' written by skywriter over Sydney

A skywriter has been spotted writing 'Vote No' in the sky over Sydney in response to the same-sex marriage campaign.

Many people expressed outraged online at the thought of someone paying a sky writer to scrawl the message over Sydney.

However, the writing didn't last long due to the strong winds in the city on Sunday morning.

It's unclear whether there is just one 'Vote No' written or multiple as there have been sightings all over the city.

One Twitter user posted "and now there's a third".

Seven News Online has contacted local sky writing companies, but has not had a response.


'No' campaign launches in Sydney

Meanwhile, Senator Corey Bernardi spearheaded the anti same-sex marriage campaign's national launch in Sydney on Saturday night, joined by prominent coalition politicians Matt Canavan and Concetta Fierravanti-Wells, who all took to the podium under blue and pink lights to champion the no vote.

An estimated 1000 people, many with shirts and placards bearing the slogan "It's ok to say 'no'", filled the International Conference Centre at Darling Harbour.

Senator Bernardi, who received a standing ovation, warned the audience of "weaponised" anti-discrimination laws and "legal warfare" against supporters of traditional marriage if the Marriage Act is changed to include same-sex couples.

Free speech was under attack from those seeking to redefine marriage, and their mission would have predictable consequences, he added.

"We're under assault because we're on the right side of legal and moral history," he said.