The Bulgarian government plans to offer for sale minority stakes in three free trade zone operators for non-cash payment instruments, it said on Wednesday. The state will offer for sale minority stakes in the operators of the free trade zones of Burgas, Varna and Plovdiv, the government said in a press release after a weekly meeting. The government opted to sell the stakes for non-bash payment instruments in the hope of attracting investor interest after several unsuccessful sale attempts in the 2009-2013 period, it added.