ISLAMABAD, May 18 (APP): President Asif Ali Zardari on Friday summoned a joint sitting of the Parliament on May 21 at 5 pm, that will be addressed by Turkish Prime Minister Recep Tayyip Erdogan. The President has summoned the joint sitting on the advice of the Prime Minister. The Turkish Prime Minister will be on a three-day visit to Pakistan. Prime Minister Gilani was earlier invited to address the Turkish parliament, during his last visit to Turkey.