US President Donald Trump has hailed the special relationship between his nation and Britain as he paid a gushing tribute to King Charles during his historic second state visit, calling it one of the highest honours of his life.

It was a day of unprecedented pomp for a foreign leader.

Trump and his wife Melania were treated to the full array of British pageantry. Then, the president sang the praises of his nation's close ally.

"The bond of kinship and identity between America and the United Kingdom is priceless and eternal. It's irreplaceable and unbreakable," Trump said in a speech during a lavish banquet at Windsor Castle, family home to British monarchs for almost 1000 years.

Referring to the so-called special relationship between the two nations, Trump said: "Seen from American eye

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