The prime minister has hailed UK-Irish co-operation on Northern Ireland.

Gordon Brown was in Belfast on Thursday to attend an Ulster investment conference.

Also addressing the 120 US senior executives were new Irish taoiseach Brian Cowen, outgoing first minister Ian Paisley, and deputy first minister Martin McGuinness.

At Stormont, Brown and Cowen united in their message that Northern Ireland has put behind it the problems of the past and is now in a strong position to enjoy sustained economic growth.

Brown said: "The talks we have had today show the relationship between our two countries is going to be stronger than ever."

"Just as Tony Blair and Bertie Ahern worked last year to move things forward, so Brian Cowen and I will work together to move things forward in the next year," he added.

The taoiseach stated: "The prime minister and I will work diligently and assiduously together to do all we can to assist all that is going on here."

He had earlier explained that the "conference is a timely reminder that our destiny on this island cannot be secured in isolation from the rest of the world".

These sentiments were echoed by Paisley, who said: "Today is a good news day for us. We had good news yesterday and we have good news today. We are on the right road and will keep right on to the end of the road and see Ulster prosperous."

And speaking via a video link, US president George Bush pledged his support for Northern Ireland, describing it as "open to foreign investment".

"Americans have recognised the expanding opportunities in Northern Ireland," Bush stated. "More than 160 US investors now own businesses in your region, and last year, 130,000 Americans visited your beautiful land."

Jose Manuel Barroso, the European Union president, also spoke via video link.

"I am sure that foreign investors already established in Northern Ireland will soon be joined by more, and then Northern Ireland will take its place on the map as a region embedded in a broader network in a new Europe which is the foundation stone for our future prosperity," he said.