What is the fine-grained topic of the following text: As a convinced advocate of multilateralism, Angela Merkel urged the reformation of the WTO which needs to take account not only of getting rid of trade barriers and tariffs but also of the non-tariff barriers, such as environmental requirements, health protection or different technical standards. Only return the topic.
Angela Merkel's advocacy for WTO reformation considering trade barriers, tariffs, and non-tariff barriers.