By Martina Purdy
BBC NI political correspondent
Ian Paisley and Martin McGuinness appear to have charmed not only each other, but also George W Bush.
The president spent more than one hour with the ministers
The president had planned to spend 15 minutes with the first and deputy first minister, long enough to have his picture taken and wish them well in their new power-sharing pact.
"He's obviously been taken with them," said a long-time member of the Washington media, after it emerged the president had spent more than an hour with the Stormont ministers.
With the cameras running in the Oval office, the president sat between Ian Paisley and Martin McGuinness - and certainly made clear he had a sense of occasion.
It was not that long ago after all that Ian Paisley was refusing even to sit in the same room as Martin McGuinness, the former IRA leader he had branded a terrorist.
Mr Bush told the gathering that as president he was privileged to see history unfold and this was one such occasion.
He added: ''These two men have dedicated themselves to embettering Northern Ireland through courage and conviction and desire to put aside the past and focus on a hopeful future.
"And so I want to welcome you all here and I congratulate you for seizing the moment and writing a hopeful chapter.''
No one seemed to mind that ''embettering'' was not actually a word, as the sentiments seemed sincere.
Martin McGuinness, reflecting on his relationship with the first minister, declared: ''Up until the 26 March this year, Ian Paisley and I never had a conversation about anything - not even about the weather - and now we have worked very closely together over the last seven months and there's been no angry words between us.
"This shows we are set for a new course.''
Ian Paisley suggested that the ''squabbles'' as he put it were in the past, and that the new regime was united in a common cause: ''There will be a fight for peace. You have to fight for peace. And we are dedicated to that.''
Mr Bush seemed to have a particular rapport from the outset with Mr Paisley and chuckled heartily when Ian Paisley thanked the United States for its assistance, before adding that Northern Ireland had done a lot for America also.
He no doubt was referring in part to the presidents that had hailed from Ulster, a point he had repeated at another reception earlier in the week.
The extended talks are thought to have focused on economic measures to bolster the Northern Ireland economy.
One idea focussed on exchange programmes which could mutually benefit Northern Ireland and America.
A source close to the first minister also told the BBC that the president had been asked to remember at Christmas members of the Royal Irish Regiment serving in Iraq.
After the meeting, the two ministers held a brief news conference before departing for the airport.
Mr Paisley was so happy he even thanked the media for its interest.
Ian Paisley said the five day investment mission had been a great success.
"I couldn't leave this city in a better frame of mind....It's a very happy way we leave.
"This has been a tremendous meeting for us. This has been a cracker of a meeting," Mr McGuinness added that he was tremendously encouraged, not least by the presidential endorsement for next May's investment conference.
'Northern Ireland plc'
"I think people here are delighted and overjoyed, as we are delighted and overjoyed."
Even before the White House visit, the ministers were on a high, having had a very positive meeting with Presidential hopeful, Hillary Clinton.
She promised that as president she would ensure an open door at the White House for the ministers.
That was present enough, but she also gave them each framed photographs of the 1995 Clinton Christmas visit to Belfast City Hall and the Guildhall.
The inscription included a few of poet Seamus Heaney's famous lines: ''... once in a lifetime the longed-for tidal wave of justice can rise up and hope and history rhyme.''
For Danny Kennedy, the Ulster Unionist chairman of the minister's committee there was no sour note to be struck.
Mr Kennedy had joined the ministers and presented Senator Clinton with a scarf made in Newry.
He too declared the five-day investment drive a successful one for Northern Ireland plc.