In his article, Lord Mandelson argued Britain’s “Atlantic alliance” cannot “enjoy its glorious past” but must instead “adapt to new threats and technological challenges”.
He wrote: “America’s allies need to hear the message the American people have sent and calibrate their partnerships in order to work with and alongside the US to stand up for the joint interests that unite us.
“Trump’s great skill as a political campaigner is to tap into sections of an electorate that feel unheard.”
The Republican candidate’s “resounding victory” should be viewed by allies as a “significant opportunity to bring entrepreneurial thinking and urgency to resolving foreign policy that needs real-world solutions,” he added.
“The Trump administration will rightly put the needs of Americans first,” Lord Mandelson said.
“But in its closest allies, it will find old partners open to new ways of dealing with the current world – to protect, enrich and build opportunities for Americans and our own citizens alike.”
Lord Mandelson will replace Dame Karen Pierce, whose term in Washington DC is due to end around the time Trump enters the White House on Monday.
He also echoed strong US criticism of both China and Iran.
Lord Mandelson – who once chaired a public body supporting UK-China relations – said the current Chinese government was “more aggressive abroad and controlling at home” in a way that “directly challenges Western governments and our values”.
He described Iran as a “thoroughly malign force” in the Middle East and added: “We must not ever allow it to become nuclear armed”.
