US President Donald Trump highlighted the important role of interpreters during negotiations with world leaders, including Russian President Vladimir Putin and Chinese leader Xi Jinping, speaking at the "Shield of America" summit.

"Interpreters are very important. You know, if you have a bad interpreter, you think everything went well: 'Well, I had a great conversation with that person.' Or: 'How well did I speak with Putin today? Did I speak well with Chairman Xi?'" Trump said.

The US president also recounted a case where he noticed that an interpreter had significantly shortened his long phrase during a conversation with an influential foreign leader.