Many Indian cement companies have decided to extend their 10-day production holiday across the country, following delay in the expected rise in demand and prices.  The production halt, already in its 13-day, will be extended by at least another week, senior industry officials said.  Industry sources said, "The companies had decided to freeze output to push up prices and to reduce their huge inventory pile-up. But since the expected demand increase has not taken place, production is likely to remain suspended until next week.