They might look a little rough around the edges but American heavy metal band Metallica have hearts of pure gold.

The musicians are the latest in a whole slew of international celebrities to throw their support behind charities supporting Australian bushfire relief.

The band announced they are donating $750,000 to NSW Rural Fire Service and Country Fire Authority in Victoria through their charitable foundation All Within My Hands, via Instagram on Wednesday.

Donation: Heavy metal band Metallica has pledged to donate $750,000 to firefighting agencies in Australia

In a statement released by the band, they said they felt 'overwhelmed' by the wild fires which are sweeping through the country.

'The resulting destruction and devastating effects on all residents, animals, the environment and the incredible land in Australia is truly heartbreaking,' they said.

Then they urged others to 'join us' to 'do whatever' they could to assist while providing information and links to the respective firefighting organisations.

'Overwhelmed' Metallica released a statement to Instagram on Wednesday where they said they were 'overwhelmed' by the devastation in Australia and urged fans to 'join' them by donating to NSWRFS and CFAVic

Fans overwhelming took to social media to thank the band.

'You are truly the best! God bless you all' one woman commented.

'Absolutely amazing guys!! Thank you from Australia! Can’t wait for you guys to come back,' a man commented.

Another fan was quick to suggest further ways the band could could help raise funds for bushfire relief charities in Australia.

Cancelled: The donation comes three months after Metallica was 'devastated' to indefinitely postponed the Australian and New Zealand leg of their World Wired Tour after lead singer James Hetfield, 56, re-entered rehab to treat an 'addiction'

'Ya'll should do a fundraiser concert with a bunch of other rock bands like Live AID but you donate funds to Australians affected by the fires,' they wrote.

Other users quickly suggested U2, Pink and Guns N' Roses might be persuaded to join in, if Metallica did go ahead and plan a aid relief style concert.

The donation comes three months after the band was 'devastated' to indefinitely postpone the Australian and New Zealand leg of their World Wired Tour after lead singer James Hetfield, 56, re-entered rehab to treat an 'addiction'.

The catastrophic bushfire season in Australia has so far claimed at least 25 lives, destroyed 2,000 homes and killed close to a billion animals.