'Let me know' if you visit: Trump's casual invite to prime minister leaves civil servants aghast

Known for bucking tradition, president-elect Donald Trump reportedly conducted himself outside the parameters of historical precedent in his first conversation with Theresa May, telling the UK prime minister she “should let [him] know” if she swings by the United States.

"If you travel to the US you should let me know," Trump told May, according to the UK paper the Independent.

Civil servants were reportedly aghast by leaked transcripts revealing the conversation between Trump and May, particularly the president-elect’s nonchalant approach towards inviting a world leader over to his country. The Daily Mirror called it “bizarrely un-Presidential.”

According to theIndependent, during his 10-minute conversation with May, Trump also “disclosed that he was a big fan of the Queen and asked for his regards to be passed on to Britain’s longest reigning monarch.” The paper added Trump’s “extraordinarily casual” conversation with May “stunned civil servants."

May is one of the first UK leaders to speak with Trump, though she trailed far behind far-right UK Independent Party leader Nigel Farage, a major proponent of the Brexit vote who acted as de-facto Trump surrogate during the presidential election. Trump has hailed his win against Hillary Clinton as “Brexit times three.”