Before Mr Trump Jr's television appearance his father sent a tweet calling him a "great person who loves our country!"

Meeting to be examined by investigations

The emails between Mr Trump Jr and Mr Goldstone will become central to Congress-led and special counsel investigations into potential collusion between Russia and the Trump campaign.

It is probable that Mr Trump Jr, Mr Kushner and Mr Manafort will be required to reveal what was said at the meeting under oath.

"The American people need to know that our president is acting on their behalf and not acting because he has a fear that the Russians could disclose things that would harm him or his family," said Adam Schiff, the top Democrat in the House Intelligence Committee.

Lindsey Graham, a senior Republican senator, said: "That email is disturbing. I know Donald Trump Jr is new to politics, I know that Jared Kushner is new to politics, but this is going to require a lot of questions to be asked and answered.

"Any time you're in a campaign and you get offered from a foreign government to help your campaign, the answer is no. So I don’t know what Mr Trump Jr's version of the facts are. Definitely he has to testify."