The White House has revealed that US President Donald Trump met his Russian counterpart, Vladimir Putin, for a second time on July 7 in a previously undisclosed discussion, which lasted “nearly an hour”.

National Security Council spokesman Michael Anton rejected concerns that Mr Trump was not with any other US officials and used Mr Putin’s translator. “The American translator accompanying President Trump spoke Japanese. When President Trump spoke to President Putin, the two leaders used the Russian translator, since the American translator did not speak Russian.”

The White House statement said the conversation took place in full view of other world leaders and their spouses at a dinner hosted by German Chancellor Angela Merkel during the G20 summit. Trump was seated near Japanese Prime Minister Shinzo Abe and Abe’s wife, while first lady Melania Trump was seated next to Putin.

“During the course of the dinner, all the leaders circulated throughout the room and spoke with one another freely. President Trump spoke with many leaders during the course of the evening. As the dinner was concluding, President Trump went over to Mrs Trump, where he spoke briefly with President Putin.”

The discussion came after their scheduled, two-hour-long bilateral meeting earlier that day.

The disclosure has raised questions about what the pair talked about, who was present and why the meeting was not previously mentioned.

Mr Trump took to Twitter to criticise the suggestion that there was anything improper about his dinner chat with Mr Putin, declaring the story “fake news” and that all the G20 leaders and spouses were invited to the dinner. Trump tweeted, following it up with another, saying: “The Fake News is becoming more and more dishonest! Even a dinner arranged for top 20 leaders in Germany is made to look sinister!”

A second White House official denied there was a “second meeting” between Mr Trump and Mr Putin, describing a “brief conversation at the end of a dinner”.

“The insinuation that the White House has tried to ‘hide’ a second meeting is false, malicious and absurd,” the official said.