AUSTRALIA has been sold a “complete and utter lie” on the reality of a post-Brexit free trade agreement (FTA) that ignores indisputable facts of geography and is “nonsense on stilts”.

That’s according to former UK deputy prime minister Nick Clegg, who was once head of the Liberal Democrats and is now working to reverse Brexit which he claims is not “inevitable”.

The former MP who lost his seat in the 2017 election has written a book on How to Stop Brexit and said despite what Australia might think, “romanticising” Commonwealth connections doesn’t make up for cold, hard, economic reality.

“We will never, ever, conduct trade with countries on the other side of the planet as intensely and as effortlessly as we can with our near neighbours. That is a complete and utter illusion,” he told reporters in London.

“One of the most pernicious lies … of the Brexiteers, is that there is this … utopia of new trade deals with far-flung places which will somehow replace the trade that we will lose by yanking ourselves out of the customs union and single market in our neighbourhood. It is complete and utter nonsense on stilts.”

The comments come two weeks after Australian Foreign Minister Julie Bishop visited London to spruik a potential FTA that she said the UK could use as a stepping stone to join the trans-Pacific Partnership.

“Australia is very keen to pursue negotiations for a free-trade agreement with the United Kingdom,” she said at the time, while also discussing visa access with her UK counterpart, Boris Johnson.

Australia negotiating an FTA with the UK depends on it leaving the customs union as part of the Brexit deal. That prospect was dealt a blow this week when UK Labour leader Jeremy Corbyn said his party would back staying in.

However, Mr Clegg rubbished the idea that deals with “far-flung places” could replicate the benefits of free-trade with the EU the UK already enjoys. The EU currently makes up more of UK imports and exports than the rest of the world combined.

“Of course it’s important because of the great affinity that exists between the countries of the Commonwealth and most especially with our kith and kin on the other side of the planet,” he said about trade between the nations. “But we shouldn’t turn that into a form of romanticism which ignores the realities of how economies conduct trade with each other. “

“We are tectonically and geologically and geographically a European nation. We’re not going to be plucked out of the English Channel and pulled by tugboat to be located somewhere between Australia and New Zealand or to be adjacent to Massachusetts. We are a European nation, and we trade more with our European neighbours by far than any other.”

Mr Clegg is now part of a movement working to challenge the idea the UK is set to leave the EU by March 2019. He told reporters the “deeply dishonest intellectual project” could be doomed to fail under the weight of its own contradictions, young people finding their voice and MPs using a vote in Parliament at the end of the year to throw out the deal.

The comments come during a significant week for negotiations in which UK PM Theresa May met with EU Council President Donald Tusk in London ahead of a key speech setting out her plans.

Mrs May’s task of reconciling diametrically opposed visions for Brexit has been described as “three-dimensional chess” and is complicated by factors like the Northern Irish border and EU insistence the UK cannot “cherry pick” terms.

On Thursday, former prime minister Tony Blair said Mrs May is stuck between a rock and a hard place as sacrificing being in the EU customs union will mean taking an economic hit.

“The problem that she (Mrs May) has is that there is no way ’round the dilemma,” he said. “What she thinks is that it’s possible to get the European Union to give us access to Europe’s markets without the same obligations that the rest of Europe has in the single market.

“That is not possible. It’s not a question of a tough negotiation or a weak negotiation, it literally is not going to happen.

“So the dilemma you have is you’re either going to have to stay close to Europe to minimise economic damage, in which case you abide by Europe’s rules, or you’re free from Europe’s rules, in which case you’re going to have economic damage.”