Revenge porn, or image-based abuse, is the sharing of explicit images without consent.

The online portal provides advice on getting the images removed, reporting the abuse to authorities and pursuing legal action.

The country's eSafety commissioner said 20% of Australians aged between 16 and 49 have experienced image-based abuse.

Young women and indigenous Australians were more likely to be victims.

The same research found that 76% of victims took no action, often because they didn't know what to do.

In a statement, communications minister Mitch Fifield said the $4.8m (£2.8m) portal was "world-first", although the Californian government provides a similar service and non-government organisations elsewhere provide similar resources.

Mr Fifield also said the government is considering introducing civil penalties for perpetrators or websites that distribute revenge porn.

There are already specific laws against revenge porn in all but three Australian states and territories, and telecommunications laws have also been used to prosecute offenders.

Revenge porn is illegal in the UK, Canada, New Zealand and Japan, and in most US states.