BANGKOK -- Fast food operators in Thailand were braced Tuesday for a drop in sales as a boycott of U.S. made goods, called by Thai Muslim groups in protest at military strikes on Afghanistan, takes hold. "War is bad for everyone. Even though we're a us brand, all our workers are Thais, including Thai Muslims," said Kittiwat Jaturuntanon, director of operations at McThai Co. Ltd., the local franchise of McDonald's. Kittiwat told ***The Nation*** newspaper that McThai had increased the number of security personnel at its outlets to ensure clients and employees were safe. "Our focus now is to ensure the high quality of customer service. In the end, customers will decide for themselves," he said. An alliance of religious groups declared the boycott over the weekend, urging Thai Muslims to steer clear of McDonald's, Kentucky Fried Chicken, Pizza Hut, Coca-Cola, Pepsi, Nike, Citibank and American Express. Discount stores owned by the United States' European allies were also to be shunned. Tricon restaurants (Thailand), which operates 280 Kentucky Fried Chicken and 85 Pizza Hut outlets nationally, said the boycott was likely to make a dent in revenue from this week. "In terms of sales I would say that in the short future, probably a couple of days to come, there will be some effect," a company spokeswoman told AFP, adding that the firm hoped the drop would be limited. The Tricon spokeswoman said the boycott was misguided as it would hurt ordinary Thais employed by the multinational. "We can't deny that we are American because KFC is an American brand," she said. "But KFC in Thailand is operated 100 percent by Thais and we employ almost 10,000 Thai employees in our network." Thailand's small Muslim community has been vocal in its opposition to the U.S.-led campaign, but protests focused on the sprawling U.S. Embassy compound in Bangkok -- the second-largest in the world -- have so far been peaceful. Muslims from across Thailand are to meet over the weekend to press the government for answers on whether a Thai airbase is being used for the strikes which are aimed at uprooting the Al-Qaeda terrorist network in Afghanistan. Thai Muslims live mostly in five southern provinces bordering Malaysia -- Pattani, Yala, Narathiwat, Satun and Songkla -- and make up about five percent of Thailand's 62 million predominantly Buddhist inhabitants. Security in the southern provinces has been stepped up amid the condemnation of the U.S. actions by local Muslims.