Britain's outgoing Prime Minister Theresa May | Fabrice Coffrini/AFP via Getty Images Outgoing UK diplomat slams ‘chaotic politics’ and Brexit ‘shambles’ In diplomatic cable seen by POLITICO, high commissioner says Singapore’s leaders wonder what happened to ‘the nation they admired for stability, common sense, tolerance and realism.’

LONDON — The outgoing British high commissioner to Singapore has warned that the Asian city-state's leaders are "baffled by the U.K.'s chaotic politics" and that Brexit is doing lasting damage to the U.K.'s reputation.

In a devastating assessment of the damage Brexit is doing to the U.K.'s global reputation, Scott Wightman, one of the country's most senior diplomats, said major investors told him the balance of future investment in Europe "will inevitably be weighted more towards Germany and France," with post-referendum political risk now their "principle consideration."

His comments also cast doubt on the U.K.'s Global Britain strategy aimed at averting the economic damage of Brexit by using the country's network of influence and trade links around the world.

In a confidential Foreign and Commonwealth Office diplomatic telegram, seen by POLITICO, Wightman, who has been in the job since 2015 but posted his last tweet as British high commissioner on Tuesday, said the Singapore-U.K. Partnership for the Future, an initiative to improve ties that was launched by Foreign Secretary Jeremy Hunt in January, was being used in the “classic manner of the illusionist.”

"Like posts across the network and departments in the U.K., we’re performing minor miracles for U.K. interests faced with the utter political shambles of Brexit," he said. Singaporean ministers are "mystified as to how our political leaders allowed things to get to this pass," he added.

Wightman also likened the damage to Britain's reputation in the last three years to the battle known as the Fall of Singapore in 1942.

In a sign of how closely the ongoing Tory leadership race is being watched in capitals across the world, Wightman said Cabinet ministers had asked him in farewell calls how “the claims of candidates to succeed as leader of the Conservative Party are to be squared with the parliamentary arithmetic and established EU positions.”

Wightman also likened the damage to Britain's reputation in the last three years to the battle known as the Fall of Singapore in 1942.

He said the battle showed the "complacency and arrogance of colonial leadership."

"It transformed their view of British imperialism," he added. "Things were never the same again. The last three years have done the same for Singaporeans’ view of contemporary Britain. The nation they admired for stability, common sense, tolerance and realism grounded in fact, they see beset by division, obsessed with ideology, careless of the truth, its leaders apparently determined to keep on digging.

"I fear many around the world share their view," he said.

Wightman, a diplomat since 1983, has worked in British embassies in Beijing, Paris and Rome and was U.K. ambassador to the Republic of Korea. He was director for the Asia Pacific region in the Foreign Office from 2008 to 2010.

He said that while the U.K. benefits from "deep reserves of affection and goodwill," and that Singapore could be expected to work constructively with the U.K. irrespective of where it ends up on Brexit, he added: "Whatever we may say in public about Global Britain, we must not kid ourselves about the lasting damage that has been done to the U.K. in the eyes of Singaporeans and doubtless many others around the world."

A Foreign Office spokesperson said: “The whole of government is working to deliver a successful Brexit and the FCO is at the forefront of this effort.”

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