Confusion surrounding Trump's talks with foreign leaders1:05

As world leaders look to meet and talk with U.S. President-elect Donald Trump, some officials say they are confused as to how to contact the soon-to-be U.S. leader and his transition team. Natasha Howitt reports.

US President-elect Donald Trump has made a slip-up while taking calls of congratulations from world leaders. Picture: Sara D. Davis/Getty Images)

PRESIDENT-elect Donald Trump has a bit of work to do when it comes to playing the part of a world leader, a leaked transcript of his phone call with the British Prime Minister has revealed.

The conversation with Britain’s new leader Theresa May lasted for only 10 minutes, but even in that time Mr Trump managed to make a slip-up that has seen him labelled “un-Presidential”.

During the conversation, the President-elect extended a bizarrely casual invitation to Mrs May.

“If you travel to the US, you should let me know,” he told the British PM, according to The Times.

The comment has raised eyebrows among officials and observers, who have remarked the comment made Mr Trump seem oblivious to the months of preparation that go into an overseas visit of a country’s leader.

British Prime Minister Theresa May called Mr Trump to congratulate him. Picture: Niklas Halle’n/AFP Photo

British Prime Minister Theresa May called Mr Trump to congratulate him. Picture: Niklas Halle’n/AFP PhotoSource:AFP

‘You should let me know’: Donald Trump is being ridiculed for his invitation. Picture: Gary Gershoff/Getty Images

‘You should let me know’: Donald Trump is being ridiculed for his invitation. Picture: Gary Gershoff/Getty ImagesSource:Getty Images

According to the Mirror, an overseas trip attended by Mrs May would cost tens of thousands of pounds and involve the use of the Royal Airforce luxury Voyager Jet that is reserved for such occasions.

The flippant comment has seen Mr Trump slammed, and the sometimes vicious British press has reacted accordingly.

The Mirror labelled the comment “bizarrely un-Presidential”, and pointed out the invitation sounded “more like a holiday than a state visit”.

According to the Guardian, the invitation left civil servants “befuddled”.

Social media users were also amused by the conversation, with one remarking “Is he offering a state dinner of a discount at the Trump hotel?”

According to the transcript, which the Prime Minister’s Office has not verified, Mr Trump also asked Mrs May to pass on his regards to the Queen during her next audience at Buckingham Palace.

He reportedly said his late mother, Mary, who was born in Scotland, was a big fan of the monarch.

During the Thursday phone call, the President-elect called the UK a “very special place for me and my country”.

Australian PM Malcolm Turnbull called in a favour to get onto Mr Trump early. Picture: Prime Minister’s Office

Australian PM Malcolm Turnbull called in a favour to get onto Mr Trump early. Picture: Prime Minister’s OfficeSource:Supplied

Mr Trump has been doing the rounds of world leaders receiving congratulatory phone calls of since his election last week.

While those like Mrs May have waited their turn to be connected through official diplomatic channels, it was revealed yesterday that Australian Prime Minister Malcolm Turnbull jumped the queue to become the second leader to speak with Mr Trump after his election by calling in a favour.

Mr Turnbull had instructed US ambassador Joe Hockey to ask golfing legend and friend of Mr Trump, Greg Norman, for the President-elect’s private line.

The favour facilitated what Mr Turnbull has repeatedly described as a “very warm” discussion.

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