'Don't be a fool! I will call you later': Read Trump's 'juvenile' letter to Erdogan in full

A new letter has cast light on Donald Trump's unconventional approach to foreign relations.

US President Donald J Trump Source: AAP

Critics of US President Donald Trump have branded a letter he sent to Turkish President Recep Tayyip Erdogan as "juvenile" and "irresponsible" diplomacy.

On Thursday, a 9 October correspondence emerged, in which Mr Trump warned Mr Erdogan about the consequences of invading northern Syria.

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