ISTANBUL - The multifaceted relations between Pakistan and Turkey are burgeoning in defence field as the latter has agreed to modernise its F-16 fleet which will cost Islamabad $75 million, said a senior official of Turkey-Asia Pacific Councils of Foreign Economic Relations Board (DEIK) on Saturday. Both countries have struck a deal in an aviation project under which Istanbul will modernise Pakistan’s air fighter planes and some of them have already been flown to Turkey, said Volkan YUZER Regional Coordinator while giving briefing to a group of visiting journalists. He said Turkey was manufacturing engines of the F-16 jets, besides making some of their spare-parts as well.