"The use of the terms 'secret' or 'confidential' for this meeting provokes absolute surprise and incomprehension," said Kremlin spokesman Dmitry Peskov yesterday.
The meeting had been "officially accepted" by diplomatic channels, he added in comments reported by the Russia's TASS news agency.
"There was no secret and confidential meeting," he said. "To say so is absolutely absurd."
The White House confirmed US media reports of the previously undisclosed meeting on Tuesday and Trump took to Twitter to blast the suggestion that there was anything improper about his dinner chat with Putin.
The Trump administration has been besieged by allegations that the president's closest advisers colluded with Russia to win the 2016 presidential election.
Trump's eldest son Donald Jr recently released emails showing he held a meeting during the campaign with Kremlin- connected figures, hoping to get dirt on his dad's rival rival for the White House, Hillary Clinton.