Australia has a major role to play in helping Britain rebuild fractured trade relationships after last year's surprise vote to leave the European Union (EU), an influential figure from the Tony Blair era says.
Former Labour cabinet secretary Peter Mandelson said Australia could help Britain keep its place on the world stage, as the fallout of Brexit continued to create uncertainty about current and potential trade deals.
Mr Mandelson has been in Sydney and Melbourne to help lay the groundwork for a free trade deal between Australia and the UK, which remains on hold until the terms of Britain's exit from the EU are finalised.
"What I'm finding is quite of lot of bemusement about what Britain has done," Mr Mandelson said.
"We turned our backs on Australia in the 1970s order to join Europe. Now we're divorcing Europe all these decades later.
"I think many Australian business people just wonder why on earth we should throw all the sticks and all the rules up in the air without any idea where they're going to land."
Mr Mandelson, a former Northern Ireland secretary and EU trade commissioner, said, with Prime Minister Theresa May refusing to rule out a "hard Brexit", Australia could help Britain rework it's image of being protectionist and isolationist.
"One thing Australia can do for Britain is to reintroduce us to the world of trade policy and trade negotiation, from which we've been absent for nearly 50 years as we've relied on the size and the heft of the EU," he said.
"We are part of each other's DNA, we do have a special friendship.
"But with the extraordinary turn that Britain is now taking in leaving Europe, there is an opportunity to forge a further relationship built on trade realities."
Mr Mandelson was a stalwart of the "remain" campaign and made his first visit to Australia to offer advice to businesses in his role as chairman of consultancy firm Global Counsel.
He acknowledged Australia's key trade relationships were now with the United States and China, but said Australia was gifted an opportunity in the 1970s when Britain softened traditional links in favour of Europe.
"The biggest favour that Britain ever did for Australia was saying in the 1970s that the protectionist, rather isolationist exclusive relationship it had with Britain needed to end," Mr Mandelson said.
"We forced Australia through the decision of turning our backs and to going into Europe, to create an open economy and look to its own region.
"Just look at the fortune and prosperity that Australia has been able to achieve. For Britain we've got to make the same judgement that there's no future in retreating into ourselves."
However, Mr Mandelson conceded it might be in Australia's best interests to prioritise an agreement with the EU ahead of one with Britain.
'Brexit will introduce trade frictions, political tensions'
A potential flashpoint from Brexit has been the trade relationship between Northern Ireland and the Republic of Ireland which was created after decades of sectarian violence.
Mr Mandelson said the Good Friday agreement of 1998 saw Northern Ireland keep its links with the UK, while also being allowed to participate in an "all Ireland" economy without hard borders.
"What Brexit does is to just reinsert a border down the middle because when we leave the EU we won't be in a single market," he said.
"That is going to reintroduce not just trade frictions but political tensions, which could very well undermine all that we've achieved in Northern Ireland.
"I think over time people are going to have to choose between the political settlement they have and the economic future and prospects that they want."
Mr Mandelson slammed former prime minister David Cameron's decision to hold a Brexit referendum as, "not the finest hour for Britain's political elite".
"Britain's political elite was given a good kicking in the referendum and in a sense who can be surprised?" he said.
"The British people emerged from the global financial crisis bearing a lot of pain for other people's policy errors."
As the uncertainty about Brexit continues, Mr Mandelson said calling the referendum was, "an utterly irresponsible thing to do".
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