The Royal Commonwealth Society is making plans to open a branch in the United States, with a view to one day bringing America into the fold as an "associate member".

The project, which is said to be backed by the Queen, has come about in part as a result of Donald Trump's fondness for Britain and the Royal Family.

It comes amid efforts to develop the Commonwealth as a tool for building relationships on everything from foreign policy to trade, following Britain's exit from the European Union.

"The UK rather left this treasure in the attic, and forgot about it because people were so glued to Brussels," said Michael Lake, the director of the Royal Commonwealth Society.

Opening a branch in the US, Mr Lake said, would further Britain's ties with America, developing new connections between two countries who already share a common language.

Mr Lake said the plans had been hastened by the "opportunity of a new president, and the slightly dangerous but great fun opportunity that the 'Bad Boys of Brexit' offered".

In December, Mr Lake wrote a letter to Mr Trump, which was hand carried by Andrew Wigmore, a close aide to Nigel Farage, and then delivered by the former UKIP leader.