Utilize the input text as a context reference, choose the right relationship between Merkel and Germany from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

Speaking in Istanbul at a joint news conference with Turkish Prime Minister Ahmet Davutoglu, Merkel said Germany could help accelerate the path to visa-free travel to the EU for Turks and push forward Ankara's protracted EU membership talks.

Answer: headquarters_location