Steel structures supporting the 42,000 tonnes of twisted steel that make up the main stadium for the 2008 Olympics, commonly known as the 'bird's nest', have been removed in a four-day operation that ended yesterday. The 91,000-seat National Stadium, which will host the Games' opening and closing ceremonies in less than two years' time, has become known for its heavyweight budget of 3.13 billion yuan and latticework design of steel girders that have posed technical difficulties. 'The successful removal of the support structure, which is the most important stage in the building of the stadium, also marks major progress in the construction of all Olympic venues,' said Wang Gang , a deputy director of the Engineering and Construction Office for the Olympics. 'Construction of the steel structure for the bird's nest is expected to be completed by the end of November.' Mr Wang said it took engineers using 156 hydraulic jacks four days to ease away the 78 steel gantries. In a departure from Olympic organisers' usual sensitivity - and highlighting officials' confidence that the engineering work had been successful - Beijing Television, Shanghai's Dragon TV and the Phoenix TV yesterday transmitted a live broadcast of the final removal. 'From today on, the stadium can stand on its own feet,' said Hou Zhaoxin, a leading expert at the Olympic projects construction headquarters, during the four-hour TV programme. Zhang Hengli , deputy general manager of the National Stadium Co, said: '[The removal of the support structure] was the most technically challenging part of the building of the stadium. 'I think if everything goes as expected, there won't be any problems for the rest of the project.' Mr Zhang was confident the stadium, scheduled for completion late next year, would be 'stable and safe' to stand an earthquake measuring eight on the Richter scale. Work was under way and going according to plan on all 31 competition venues to be built or renovated for the Olympics, including another technically challenging project, the National Aquatics Centre, which is also known as the Water Cube, Mr Wang said. 'The main structures of most venues are expected to be completed this year,' he said.