2009 G20 London summit a force for good in the medium term." Leaders of the member countries began to prepare for the London Summit months before the effective date, notably with two official meetings dedicated to that preparation, one held in Berlin, Germany, on 22 February 2009 for European leaders, and another in Horsham, Sussex, United Kingdom, on 14 March 2009 for Finance Ministers. Leaders of the four European Union member countries of the G20, the United Kingdom, Germany, France and Italy along with the two largest European non-members, Spain and the Netherlands, met in Berlin on 22 February 2009 to prepare for the
2018 G20 Buenos Aires summit China related to resolving the escalating 2018 China–United States trade war were a central issue of the summit. On Friday 30 November, ahead of the formal start of the summit, Presidents Peña Nieto and Trump and Prime Minister Trudeau signed the United States–Mexico–Canada Agreement (USMCA), the successor treaty to the 1994 North American Free Trade Agreement (NAFTA). The (CLACSO) and organized a counter-summit, called the First World Forum of Critical Thinking, which took place in the week leading up to the G20 event. It was attended by other politicians such as former Brazilian president Dilma Rouseff, Bolivian vice president Álvaro