The government says a number of non-EU countries have already asked for a deal
Australia has called for a free trade deal with Britain as it plans its withdrawal from the European Union following June's referendum result.
The move is seen as a boost to new British Prime Minister Theresa May, who described the call as "very encouraging" and insisted it showed Brexit could work for the UK.
She spoke to her Australian counterpart Malcolm Turnbull, who said he wanted to open up trading between the two commonwealth countries.
Mrs May has told the UK's International Trade Secretary Liam Fox to begin exploring options but admitted Britain could not sign any deals while it was still a member of the EU.
She has vowed to embrace "the opportunities to strike free trade deals with our partners across the globe".
She added: "It is very encouraging that one of our closest international partners is already seeking to establish just such a deal."
"This shows that we can make Brexit work for Britain, and the new Secretary of State for International Trade will be taking this forward in the weeks and months ahead."
Dr Fox, who backed Brexit, has claimed a number of non-EU countries have already asked Britain for a trade deal.
He said he was "scoping about a dozen free trade deals outside the EU to be ready for when we leave".
He claimed Britain has opened "very fruitful" trade talks with Canada.
And he is preparing to visit the US to make sure Britain is not at the back of the queue in trade talks, as President Barack Obama suggested before the referendum.
He told The Sunday Times (UK): "We've already had a number of countries saying, 'We'd love to do a trade deal with the world's fifth biggest economy without having to deal with the other 27 members of the EU'."
Mrs May has told Scottish First Minister Nicola Sturgeon she would not trigger Article 50 to leave the EU before getting UK-wide agreement.
But this could prove a challenge as Scotland voted overwhelmingly to remain in the EU and Mrs Sturgeon has vowed to stay in it.