They added that steel production may be further curbed during the winter and spring as more local governments come out with fresh plans to curb pollution. "The main trigger for the better performance is the overall decrease in steel production and supply," said Xu Xiangchun, information director and analyst with iron and steel industry consultancy Mysteel.com. Though steel prices have been fluctuating, they have been maintaining a strong upward momentum," she said, adding the center's indexes for composite steel prices, long steel prices and flat steel prices for the third quarter rose by 5.2 percent, 8.4 per-cent and 2.8 percent respectively over the second quarter. The rise in steel prices has also been supported by stable market demand and low steel inventories, she said. According to Xu, the steel prices could surge further in the fourth quarter as supplies shrink further due to the production curbs.