PARIS/ATHENS (Reuters) – Prime Minister Alexis Tsipras tried to reassure euro zone partners on Thursday that Greece would stick to an extended bailout agreement with its international creditors even as a war of words rumbled on between Athens and Berlin. Tsipras used a visit to the Paris-based Organization for Economic Cooperation and Development, an inter-governmental think-tank, to make his case for a long-term restructuring of Greece’s debt while promising to implement agreed reforms.