Brad Pitt said he wanted to "kick-start" the redevelopment process

The star is backing campaign group Global Green USA on the project to find environmentally-friendly designs.

The self-confessed architecture junkie wants ideas that make the city "better" yet respect "historical traditions".

Pitt, who will lead a jury of community leaders and architects, said rebuilding work in New Orleans was "long overdue".

He said the competition's aim was to "kick off the rebuilding effort".

Thousands were left homeless after the hurricane in August

"We could possibly build something that was better and took into account the historical traditions of the city and the voices of the people and turn this into some kind of good," he said.

Organisers say the winners will be selected before the first anniversary of the hurricane on 29 August.

Entrants will have to consider energy efficiency, improved indoor air quality and the use of environmentally-friendly building materials.

Six finalists will work with local neighbourhoods on more detailed proposals for environmentally sound buildings.

"Our goal is to actually implement them and to get them built and hopefully give a kick-start to a much needed redevelopment process," Pitt said.

Baby plans

Global Green USA is already providing technical assistance for 10,000 buildings in New Orleans.

The actor, who is currently in Namibia with partner Angelina Jolie, declined to comment on the upcoming birth of the couple's first biological child and rumours they plan to marry.

"Namibia's just a country we're very fond of," he said.