Sean Spicer, the White House press secretary, did not dispute the account.
Mr Trump met the Russian diplomats on May 10, the day after he fired Mr Comey.
Mr Comey had been investigating whether there was collusion between Russia and anyone connected to the Trump campaign during last year's presidential election.
In a statement, Mr Spicer said Mr Comey's pursuit of the probe had harmed Mr Trump's ability to deal with Russia over issues including Syria and Ukraine.
Mr Spicer said: "By grandstanding and politicising the investigation into Russia’s actions James Comey created unnecessary pressure on our ability to engage and negotiate with Russia."
It emerged earlier this week that at the same Oval Office meeting Mr Trump shared with the Russian diplomats classified intelligence relating to a plot by Islamic State of Iraq and the Levant.
The intelligence had come from Israel, which had not agreed for it to be shared. Israel later stood by Mr Trump who said he had an "absolute right" to share it.
Russians 'bragged about Flynn influence'
Democrats have argued that Mr Trump's firing of Mr Comey during his Russia investigation could amount to obstruction of justice.
A special counsel, Robert Mueller, has now been appointed to investigate Russian meddling in the election.
Mr Flynn has been at the heart of the investigations over his links with Russians. According to CNN, Moscow officials bragged in conversations during the presidential campaign that they had forged a strong relationship with Mr Trump's adviser and believed they could use him to influence the Republican and his team.
Source : http://www.telegraph.co.uk/news/2017/05/19/donald-trump-called-james-comey-nut-job-said-firing-eased-great/