(Reuters) - Chinese power generation group SDIC has postponed its plans to launch an offering of global depositary receipts (GDRs) in London, the latest to succumb to market uncertainty that has hit other companies as well. "The company believes this is a prudent decision and is in the best interests of its existing and future shareholders," SDIC said in a statement on Wednesday.The London Stock Exchange has seen a number of initial public offerings (IPOs) cancelled or postponed amid market..