Turkish officials have told that Pakistan president Asif Ali Zardari and Afghan president Hamid Karzai would meet in Istanbul on Friday. Talking in Ankara, an official of the Turkish government told, on the condition of not disclosing his name, that the objective of the meeting of the Pak-Afghan presidents is the improvement in mutual relations and the increase in cooperation. This is for the second time that the heads of the two governments will be meeting in Turkey.