2009 G20 London summit London Summit and to co-ordinate their actions. The meeting was organised at the initiative of German Chancellor Angela Merkel. The leaders agreed that markets, financial institutions and the wide range of financial assets they create, and hedge funds should be subject to appropriate control. In addition, they called for effective sanctions against tax havens. They also agreed to impose sanctions against countries that intend to undermine their work. Finally, they advocated the doubling of funds available to the IMF. Finance ministers and central bankers of the G20 met in Horsham on 14 March 2009 to prepare for the London Summit.
2017 G20 Hamburg summit hours, prompting the deployment of special armed police forces to end the violence. On 8 July 76,000 people attended the largest peaceful protest march "Solidarity without Borders", organized by an alliance of 174 groups and organizations. On early Sunday morning, 9 July, riots continued in the Schanzenviertel though the G20 leaders had already departed; 144 rioters were arrested. In total, more than 15,000 police were deployed from across the country, while 100,000 protesters attended. Local residents believed that authorities made a mistake by having the summit in a densely populated area. Police arrested 186 people overall: 132 Germans, 8 French,