Retail cement prices across the country are set to increase of Rs5 per 50 kg bag from next week.  Domestic cement companies Gujarat Ambuja, The Associated Cement Companies, Larsen & Toubro and Grasim Industries are looking at increasing the price of the 50kg bag by Rs5 in Mumbai, to take the price of the 50kg bag to Rs 160.  Prices in Andhra Pradesh and Karnataka could also increase by Rs5 - Rs7 per 50 kg bag, while in Gujarat, retail cement prices are likely to rise by Rs5 to touch Rs117 per 50 kg bag. Cement companies had reportedly declared a 10-day production holiday in the last week of November aimed at reducing the demand-supply gap and push up prices.  The companies had planned a price jump of Rs 10 in the retail segment last week, but could implement only a Rs 5 increase, with the balance being implemented from Monday, said a cement industry analyst.  Meanwhile, Andhra Pradesh and Karnataka could see a price rise up to Rs7 to stand at Rs142 - Rs146 per 50 kg bag.