Washington: By year's end,the occupants of the International Space Station will have twice the amount ofspace for living and working and be able to carry out more outside work ontheir own, according to plans mapped out by the US space agency. 

In addition, new control centres for the station orbiting400 km above Earth are to be opened in France,Germany and Japanto allow national space programmes to monitor their growth-boostingcontributions this year. 

A new European cargo vehicle will also make its first tripto the station in July. 

The National Aeronautics and Space Administration (NASA)hopes to expand the current two-room apartment into the size of a house withfour rooms by December, said Kirk Shireman, deputy programme manager for ISS atNASA in Houston. 

The ambitious programme for 2007 underlines the push by NASAto get the space station completed by 2010 so it can scrap the aging shuttle programmeand move on to its next project of building a moon base. 

"This will be a challenging but rewarding year for thestation programme," Shireman said. 

When completed, the ISS should accommodate six astronauts,double the number it can now handle.

But the occupancy rate will go up incrementally, with onlyone more astronaut to be added by year's end, due to constraints on energysupplies on board, NASA officials said. 

Two key missions in October and December are to deliver theEuropean Space Agency's Columbuslab and the Japanese experiment module Kibo (Japanese for hope).

Their installations will mark the first growth in interior space in more thansix years. 

A two-year-plus construction delay followed the 2003 shuttleColumbia disaster,which deprived deliveries to the ISS of the large load capacity that only theshuttle has. 

Unmanned Russian spacecraft made smaller deliveries, andother Russian craft also kept the human rotation going on board until theshuttles resumed working flights last year. 

The year 2007 will also see "unparalleled roboticoperations" that will make orbiting astronauts more independent of theshuttle programme, NASA said. For the first time the station's robotic arm willhelp assemble large pressurized components.