The uncertainty has lasted more than three years since the Brexit referendum but Ms Treadell said her talks with Australians – no strangers themselves to leadership turbulence – confirmed their confidence in Britain’s future.
“Their assessment is that Britain remains an excellent bet in the medium and long term, and they just need to manage the risks of the short term because of the uncertainties,” she said.
In her first major newspaper interview since she took office in March, Ms Treadell said Australians should remember the lessons of British history if they doubted the country’s ability to navigate Brexit.
“The key point is the fundamental strength of the UK as a country. You look at our history and the periods of difficulty we have gone through before, we have always come out at the right side,” she said.
As proof, Ms Treadell nominated the decision more than a decade ago to keep the British pound and reject European monetary union, sparing the country the problems with the euro after the global financial crisis.
And Ms Treadell said Mr Johnson, dismissed by some as a chaotic populist and admired by others for leading the charge on Brexit, was well-regarded in Australia.
“I’m not going to comment on whether or not he’s a wildcard – people will have their opinion,” she said.
“What I can say is when I’ve spoken to contacts [in Australia] who met him when he visited as foreign secretary last year, that he was received extremely well and he had a very positive impact.”
Ms Treadell joined the Foreign Office in 1978 and served as high commissioner in New Zealand and then Malaysia before being named to the position in Canberra earlier this year.
The United Kingdom’s economy grew 0.3 per cent in May but shrank 0.4 per cent in April in a sign of the challenges to come in the exit from the European Union.
Doubling South Pacific footprint
While Mr Johnson’s Brexit position has been called a “mixture of fantasy and dishonesty” by his critics, one consequence will be a negotiation over a trade deal between Australia and the UK.
“While there may be a state of flux with our politics and with Brexit yet to be resolved, the strength of our relationship, the ties between our two countries remain as strong as they ever were,” Ms Treadell said.
“You might almost argue that because of the unprecedented times the UK is going through, following the referendum decision to leave the EU, it has made us realise how important the relationship is.”
Britain wants to be full-square alongside Australia and other partners to play our part.
And for anyone who thought Britain was shrinking back around the world, Ms Treadell said the country’s Pacific Uplift policy would see it gain a stronger presence in the Pacific by re-opening high commissions in Vanuatu and Tonga, while opening a new one Samoa alongside existing offices in Fiji, Papua New Guinea and the Solomon Islands.
“We’re doubling our footprint in the South Pacific,” she said.
“Britain wants to be full-square alongside Australia and other partners to play our part.”
Ms Treadell said that meant giving the people of the Pacific “more choice” in partnerships with nations that shared the values of freedom of speech, open society and Christianity compared to “those who can just deliver big infrastructure projects”.
Does that mean China? “It can mean China, yes,” she said.
‘Law is on our side’ over Iran
Ms Treadell also declared the “law is on our side” in its confrontation with Iran over the seizure of a British-flagged oil tanker in the Persian Gulf, as the Australian government rebuked the “unjustified” move.
The high commissioner said there was “no need to escalate” the dispute and seek more help from the Morrison government.
And she said the British were determined to keep up their freedom-of-navigation operations in Asia despite Chinese claims of sovereignty in the South China Sea.
The Iranian Revolutionary Guard captured the Stena Impero, which is owned by a Swedish company but flies under a British flag, and took it and its 23 crew to an Iranian port last Friday. That came in response to a British decision to seize an Iranian oil tanker in Gibraltar on the grounds it was breaching sanctions by taking fuel to Syria.
“That was a legitimate reason to detain the Iranian ship and we have made it clear we can release it if Iran guarantees that the oil is not going to Syria and breaking the sanctions,” she said.
“So the law is on our side. The law is not on Iran’s side.”
Defence Minister Linda Reynolds issued a statement on Tuesday condemning Iran’s “unjustified” behaviour and insisting on freedom of navigation for maritime trade.
“The arbitrary detention of legitimate trading vessels on spurious allegations is an abuse of the rule of law,” a spokeswoman for Senator Reynolds said.
Ms Treadell said the UK would also stand for freedom of navigation and shipping in Asia.
The Royal Navy despatched three ships to the region last year, will send another before the end of this year and is expected to maintain this “rhythm” for the long-term.
“This is our commitment to playing our role globally, and exercising the right of freedom of navigation in disputed areas is, I think, an important part of what we do,” Ms Treadell said.
The comments came amid growing concern at Chinese plans to develop a base in Cambodia.
A Royal Navy warship sailed close to islands claimed by China in the South China Sea last September and the British conducted joint exercises with the US Navy in the same international waters in January.
David Crowe is chief political correspondent for the Sydney Morning Herald and The Age.